The zipfile module can be used to manipulate ZIP archive files.
The zipfile module does not support ZIP files with appended comments, or multi-disk ZIP files. It does support ZIP files larger than 4 GB that use the ZIP64 extensions.
The is_zipfile() function returns a boolean indicating whether or not the filename passed as an argument refers to a valid ZIP file.
Notice that if the file does not exist at all, is_zipfile() returns False.
Use the ZipFile class to work directly with a ZIP archive. It supports methods for reading data about existing archives as well as modifying the archives by adding additional files.
To read the names of the files in an existing archive, use namelist() :
The return value is a list of strings with the names of the archive contents:
The list of names is only part of the information available from the archive, though. To access all of the meta-data about the ZIP contents, use the infolist() or getinfo() methods.
There are additional fields other than those printed here, but deciphering the values into anything useful requires careful reading of the PKZIP Application Note with the ZIP file specification.
If you know in advance the name of the archive member, you can retrieve its ZipInfo object with getinfo() .
If the archive member is not present, getinfo() raises a KeyError .
To access the data from an archive member, use the read() method, passing the member’s name.
The data is automatically decompressed for you, if necessary.
To create a new archive, simple instantiate the ZipFile with a mode of 'w' . Any existing file is truncated and a new archive is started. To add files, use the write() method.
By default, the contents of the archive are not compressed:
To add compression, the zlib module is required. If zlib is available, you can set the compression mode for individual files or for the archive as a whole using zipfile.ZIP_DEFLATED . The default compression mode is zipfile.ZIP_STORED .
This time the archive member is compressed:
It is easy to add a file to an archive using a name other than the original file name, by passing the arcname argument to write() .
There is no sign of the original filename in the archive:
Sometimes it is necessary to write to a ZIP archive using data that did not come from an existing file. Rather than writing the data to a file, then adding that file to the ZIP archive, you can use the writestr() method to add a string of bytes to the archive directly.
In this case, I used the compress argument to ZipFile to compress the data, since writestr() does not take compress as an argument.
This data did not exist in a file before being added to the ZIP file
Normally, the modification date is computed for you when you add a file or string to the archive. When using writestr() , you can also pass a ZipInfo instance to define the modification date and other meta-data yourself.
In this example, I set the modified time to the current time, compress the data, provide a false value for create_system , and add a comment.
In addition to creating new archives, it is possible to append to an existing archive or add an archive at the end of an existing file (such as a .exe file for a self-extracting archive). To open a file to append to it, use mode 'a' .
The resulting archive ends up with 2 members:
Since version 2.3 Python has had the ability to import modules from inside ZIP archives if those archives appear in sys.path . The PyZipFile class can be used to construct a module suitable for use in this way. When you use the extra method writepy() , PyZipFile scans a directory for .py files and adds the corresponding .pyo or .pyc file to the archive. If neither compiled form exists, a .pyc file is created and added.
With the debug attribute of the PyZipFile set to 3, verbose debugging is enabled and you can observe as it compiles each .py file it finds.
Python zip() method takes iterable containers and returns a single iterator object, having mapped values from all the containers.
It is used to map the similar index of multiple containers so that they can be used just using a single entity.
Syntax : zip(*iterators) Parameters : Python iterables or containers ( list, string etc ) Return Value : Returns a single iterator object.
Python zip() with lists.
In Python , the zip() function is used to combine two or more lists (or any other iterables) into a single iterable, where elements from corresponding positions are paired together. The resulting iterable contains tuples , where the first element from each list is paired together, the second element from each list is paired together, and so on.
The combination of zip() and enumerate() is useful in scenarios where you want to process multiple lists or tuples in parallel, and also need to access their indices for any specific purpose.
The zip() function in Python is used to combine two or more iterable dictionaries into a single iterable, where corresponding elements from the input iterable are paired together as tuples. When using zip() with dictionaries, it pairs the keys and values of the dictionaries based on their position in the dictionary.
When used with tuples, zip() works by pairing the elements from tuples based on their positions. The resulting iterable contains tuples where the i-th tuple contains the i-th element from each input tuple.
Python’s zip() function can also be used to combine more than two iterables. It can take multiple iterables as input and return an iterable of tuples, where each tuple contains elements from the corresponding positions of the input iterables.
The zip() function will only iterate over the smallest list passed. If given lists of different lengths, the resulting combination will only be as long as the smallest list passed. In the following code example:
Unzipping means converting the zipped values back to the individual self as they were. This is done with the help of “ * ” operator.
There are many possible applications that can be said to be executed using zip, be it student database or scorecard or any other utility that requires mapping of groups. A small example of a scorecard is demonstrated below.
Similar reads.
Prerequisites, step 1 — setting up the project directory, step 2 — writing your first test, step 3 — running your tests, step 4 — designing your tests, step 5 — filtering tests, step 6 — providing multiple test cases, step 7 — parametrizing tests using data classes, step 8 — testing exception handling with unittest, step 9 — using fixtures in unittest, step 10 - writing tests with doctests, final thoughts.
Python includes a built-in testing framework called unittest , which allows you to write and run automated tests. This framework, inspired by JUnit , follows an object-oriented approach and includes useful features for writing test cases, test suites, and fixtures.
By the end of this tutorial, you will be able to use unittest to write and run automated tests, helping you catch bugs early and make your software more reliable.
Let's get started!
To follow this tutorial, make sure your machine has the latest version of Python installed and that you have a basic understanding of writing Python programs.
Before you can start writing automated tests with unittest , you need to create a simple application to test. In this section, you'll build a simple yet practical application that converts file sizes from bytes into human-readable formats.
First, create a new directory for the project:
Next, navigate into the newly created directory:
Create a virtual environment to isolate dependencies, prevent conflicts, and avoid polluting your system environment:
Activate the virtual environment:
Once the environment is activated, you will see the virtual environment's name ( venv in this case) prefixed to the command prompt:
Create a src directory to contain the source code:
To ensure Python recognizes the src directory as a package, add an empty __init__.py file:
Next, create and open the formatter.py file within the src directory using the text editor of your choice. This tutorial assumes you are using VSCode, which can be opened with the code command:
Add the following code to the formatter.py file to format file sizes:
The format_file_size() function converts a file size in bytes to a human-readable string format (e.g., KB, MB, GB).
In the root directory, create a main.py file that prompts user input and passes it to the format_file_size() function:
This code takes a file size in bytes from the command line, formats it using the format_file_size() function, and prints the result or displays an error message if the input is invalid or missing.
Let's quickly test the script to ensure it works as intended:
Now that the application works, you will write automated tests for it in the next section.
In this section and the following ones, you'll use unittest to write automated tests that ensure the format_file_size() function works correctly. This includes verifying the proper formatting of various file sizes. Writing these tests will help confirm that your code functions as intended under different scenarios.
To keep the test code well-organized and easily maintainable, you will create a tests directory alongside the source code directory:
This structure helps keep your project tidy and makes locating and running tests easier.
First, create the tests directory with the following command:
Next, create the test_format_file_size.py file in your text editor:
Add the following code to write your first test:
In this example, you define a test case for the format_file_size() function within a subclass of unittest.TestCase named TestFormatFileSize . This follows the unittest framework convention of prefixing the class name with "Test".
The class includes a single test method, test_format_file_size_returns_GB_format() , which checks that the format_file_size() function accurately formats a file size of 1 GB. It uses self.assertEqual() to verify that the function's output is "1.00 GB".
With your test case defined, the next step is to run the test.
To ensure that everything works as expected, you need to run the tests.
You can run the tests using the following command:
This command runs all test cases defined in the test_format_file_size module, where tests is the directory name and test_format_file_size is the test module (Python file) within that directory.
When you execute this command, the output will look similar to the following:
This output indicates that one test was found in the tests/test_format_file_size.py file and passed within 0.000 seconds.
As the number of test files grows, you might want to run all the tests at the same time. To do this, you can use the following command:
The discover command makes the test runner search the current directory and all its subdirectories for test files that start with test_ , executing all found test functions. This approach helps manage and run a large number of tests efficiently, ensuring comprehensive test coverage across your entire codebase.
Now that you understand how unittest behaves when all tests pass, let's see what happens when a test fails. In the test file, modify the test by changing the format_file_size() input to 0 to cause a failure deliberately:
Following that, rerun the tests:
The unittest framework will now show that the test is failing and where it is failing:
The output shows that the test failed, providing a traceback indicating a mismatch between the expected result ("1.00 GB") and the actual result ("0B"). The subsequent summary block provides a concise overview of the failure.
Now that you can run your tests, you are ready to write more comprehensive test cases and ensure your code functions correctly under various scenarios.
In this section, you'll become familiar with conventions and best practices for designing tests with unittest to ensure they are straightforward to maintain.
One popular convention you've followed is prefixing test files with test_ and placing them in the tests directory. This approach ensures that your tests are easily discoverable by unittest , which looks for files starting with test_ . Organizing tests in a dedicated tests directory keeps your project structure clean and makes it easier to manage and locate test files.
If that works for you, you also have the option to place test files alongside their corresponding source files, a convention common in other languages like Go. For example, the source file example.py and its test file test_example.py can be in the same directory:
Another essential convention to follow is naming each test class with a Test prefix (capitalized) and ensuring that all methods within the class are prefixed with test_ . While the underscore is not mandatory, this is a widely adopted convention among Python users:
The names you give your test files, classes, and methods should describe what they are testing. Descriptive names improve readability and maintainability by clearly indicating the purpose of each test. Generic names like test_method can lead to confusion and make it harder to understand what is being tested, especially as the codebase grows.
Here are some examples of well-named test files, class names, and method names following this convention:
Having clear and specific names produces better test reporting, helping other developers (and future you) quickly grasp the tested functionality, locate specific tests, and maintain the test suite more effectively.
Running all tests can become time-consuming as your application grows and your test suite expands. To improve efficiency, you can filter tests to run only a subset, especially when working on specific features or fixing bugs. This approach provides faster feedback, helps isolate issues, and allows targeted testing.
Here’s how you can add more test methods and run specific subsets of your tests:
When you have multiple test files and only want to run a specific test file, you can provide the module name:
It is common to have more than one class in a test module. To execute only tests from a specific class, you can use:
The output will be the same as in the preceding section since there is only one class:
If you want to target a single method in a class, you can specify the method name in the command:
Running this command will execute only the specified method:
To streamline your testing process, unittest provides the -k command-line option, which allows you to filter and run only the tests that match a specific pattern(a substring). This can be particularly useful when you have an extensive suite of tests and want to run a subset that matches a particular condition or naming convention.
For example, the following command executes only the tests that have the "gb" substring in their names:
This command will execute only the test_format_file_size_returns_format_gb test because it contains the "gb" substring. The output will be:
You can verify this with the -v (verbose) option:
In this case, the verbose output provides additional information about each test executed, making it easier to understand which tests matched the pattern and their results.
There are times when you want to skip specific tests, often due to incomplete functionality, unavailable dependencies, or other temporary conditions. The unittest module provides the skip() decorator, which allows you to skip individual test methods or entire test classes.
The skip() decorator marks tests that should not be executed. Here’s how you can use the skip() decorator in unittest :
Save and rerun the tests:
You will see the output confirming that one test was skipped:
The unittest module provides several skip-related decorators to control the execution of tests:
Multiple test methods are often similar but differ only in their inputs and expected outputs. Consider the methods you added in the previous section; each function takes the format_file_size() function and tests it with different inputs to verify the correct output. Instead of writing separate test methods for each case, you can use parameterized tests to simplify your code and reduce redundancy.
Since Python 3.4, Python introduced subtests, which consolidate similar tests into a single method. To make use of subtests, rewrite the contents of test_format_file_size.py with the following code:
This code defines a single method to test the format_file_size() function using multiple test cases. Instead of separate test methods, it uses a list of tuples for different inputs and expected outputs, iterating through them with a loop and creating a subtest for each case using self.subTest .
Now you can run the test:
You can also modify the test to cause a failure deliberately:
When you rerun the tests, you will see more details about the failure, including the specific input and expected output:
Now that you can parameterize tests with subtests, you will take it further in the next section.
So far, you have used subtests with a list of tuples to parameterize your tests. While this approach is straightforward, it has a few issues: tuples lack descriptive names, making them less readable and unclear, especially with many parameters; maintaining and updating a growing list of tuples becomes cumbersome; and adding additional metadata or more complex structures to tuples can make them unwieldy and hard to manage.
To address these issues, consider using data classes for a more structured, readable, and scalable way to organize your test parameters. Data classes help in the following ways:
Let's use subtests with data classes by rewriting the code from the previous section:
This code defines a FileSizeTestCase class using the @dataclass decorator, which includes three attributes: size_bytes , expected_output , and id . This data class serves as a blueprint for our test cases, with each test case represented as an instance of this class.
Within the TestFormatFileSize class, the test_format_file_size method iterates through a list of FileSizeTestCase instances. Each instance contains the input size and the expected output for the format_file_size function. The self.subTest context manager runs each test case independently, providing clearer test output and making it easier to identify and debug specific failures.
Now, rerun the tests with:
The tests will pass without any issues:
With this change, your tests are now more structured and maintainable, making managing and understanding the test cases more manageable.
Exception handling is essential and needs to be tested to ensure exceptions are raised under the correct conditions.
For instance, the format_file_size() function raises a ValueError if it receives a negative integer as input:
You can test if the ValueError exception is raised using assertRaises() :
The unittest framework's assertRaises context manager checks that a ValueError is raised with the appropriate message when format_file_size() is called with a negative size. The str(context.exception) extracts the exception message for comparison.
To integrate this into the parameterized tests, you can do it as follows:
This code added two additional fields to the FileSizeTestCase class: expected_error and error_message . These fields indicate if an error is expected and what the error message should be.
A new test case with an input of -1 is included to trigger the error, with the expected_error and error_message fields set accordingly.
In the test_format_file_size() method, the code checks for the expected exception using self.assertRaises() . If an error is expected, it verifies the type and message of the exception. If no error is expected, self.assertEqual() ensures that the function's output matches the expected result.
When you save and run the tests, you will see that the tests pass, confirming that the ValueError exception was raised:
For error messages that may vary slightly, you can use regular expressions with unittest.assertRaises() :
With this in place, you can efficiently verify that your code raises the expected exceptions under various conditions.
Now that you can use unittest to write, organize, and execute tests, we will explore how to use fixtures. Fixtures are helper functions that set up the necessary preconditions and clean up after tests. They are essential for writing efficient and maintainable tests, as they allow you to share setup code across multiple tests, reducing redundancy and improving code clarity.
The topic of fixtures is extensive and best served with its article, but here, we will provide a concise introduction.
To begin with fixtures, create a separate test file named test_fixtures.py :
Add the following code:
The setUp method creates a fixture that is automatically called before each test method, ensuring consistent setup. The setUp method initializes the welcome_message attribute, making it available to all test methods in the class. The test_welcome_message method then verifies that this fixture returns the correct message by using self.assertEqual to check if the value of self.welcome_message matches the expected string.
With the fixture in place, run the following command to execute the tests:
The output will look similar to the following:
For a more practical example that uses fixtures to set up a database, consider the following code using SQLite :
The setUp method creates an in-memory SQLite database connection and initializes the users table, ensuring a fresh setup before each test. The tearDown method closes the database connection after each test, maintaining a clean test environment. Additionally, the create_user and update_email methods allow for the insertion and updating of records within the test methods, facilitating database manipulation during tests.
With the fixture in place, you can add tests to verify if creating and updating users works correctly:
The test_create_user() function validates adding new users to the database. It creates a user with a specific username and email address, then confirms the user's existence and corrects the email in the database through queries. Conversely, the test_update_email() function verifies the ability to update a user's email address. It first creates a user entry, updates the user's email, and then checks the database to ensure the email has been correctly updated.
Now run the tests with the following command:
Now that you are familiar with fixtures, you can create more complex and maintainable tests.
In Python, docstrings are string literals that appear after defining a class, method, or function. They are used to document your code. A neat feature of Python is that you can add tests to the docstrings, and Python will execute them for you.
Take the following example:
In this example, the add() function calculates the sum of two numbers, a and b . The function includes a comprehensive docstring that describes its purpose ("Returns the sum of a and b") and provides an example usage in the doctest format.
This example demonstrates how to call the function with arguments 2 and 3 , expecting a result of 5 . Docstrings with embedded doctests serve a dual purpose:
When you include a usage example in the docstring, you can use the doctest module to run these embedded tests and ensure the function behaves as expected.
Let's apply the doctest to the application code in formatter.py :
The docstring for the format_file_size() function describes its purpose, input, output, and potential exceptions. It details that the function converts bytes to a human-readable format, takes an integer size_bytes as input, returns a formatted string, and raises a ValueError for negative inputs. The examples provided show typical usage and expected results.
To see if the doctest examples pass, enter the following command:
When you run the file, you will see the following output:
The output shows that the format_file_size function passed all tests. Specifically, it correctly returned '0B' for 0 , '1.00 KB' for 1024 , and '1.00 MB' for 1048576 . All 3 tests in the function passed, with no failures.
This article walked you through writing, organizing, and executing unit tests with Python's built-in unittest framework. It also explored features such as subtests and fixtures to help you create efficient and maintainable tests.
To continue learning more about unittest , see the official documentation for more details. unittest is not the only testing framework available for Python; Pytest is another popular testing framework that offers a more concise syntax and additional features. To explore Pytest, see our Pytest documentation guide .
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
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Snowpark, offered by the Snowflake AI Data Cloud , consists of libraries and runtimes that enable secure deployment and processing of non-SQL code, such as Python, Java, and Scala. With Snowpark , you can develop code outside of the Snowflake environment and then deploy it back into Snowflake, eliminating the need to manage infrastructure concerns.
In this blog, we’ll cover the steps to get started, including:
How to set up an existing Snowpark project on your local system using a Python IDE.
Add a Python UDF to the existing codebase and deploy the function directly in Snowflake.
Validate the function deployment locally and test from Snowflake as well.
Dive deep into the inner workings of the Snowpark Python UDF deployment.
Check in the new code to Github using git workflows and validate the deployment.
Before we dive into the steps, it’s important to unpack why Snowpark is such a big deal.
Familiar Client Side Libraries – Snowpark brings in-house and deeply integrated, DataFrame-style programming abstract and OSS-compatible APIs to the languages data practitioners like to use (Python, Scala, etc). It also includes the Snowpark ML API for more efficient machine language (ML) modeling and ML operations.
Flexible Runtime Constructs – Snowpark provides flexible runtime constructs that allow users to bring in and run custom logic. Developers can seamlessly build data pipelines, ML models, and data applications with User-Defined Functions and Stored Procedures.
Spark/Pandas Dataframe Style Programming Within Snowflake – You can perform your standard actions/transformations just like you would in Spark.
Easy to Collaborate – With multiple developers working on the programming side of things, Snowpark solves an otherwise collaboration issue efficiently. You can set up your own environment in your local system and then check in/deploy the code back to Snowflake using Snowpark (more on this later in the article).
Built-In Server-Side Packages – NumPy, Pandas, Keras, etc.
Easy to Deploy – Using SnowCLI, Snowpark can easily integrate your VS Code (or any editor for that matter) with Snowflake and leverage a virtual warehouse defined to run your deployment process (we’ll also cover this later in the article).
Now with the background information out of the way, let’s get started! The first thing you’ll want to ensure is that you have all of the following:
Python (preferably between 3.8 – 3.10 but not greater than 3.10 ).
Miniconda (if you already have Anaconda, please skip).
Snowflake account with ACCOUNTADMIN access (to alter the configuration file).
Anaconda Terms & Conditions are accepted on Snowflake. See the Getting Started section in Third-Party Packages .
GitHub account.
Gitbash installed.
VS Code (Or any similar IDE to work with).
SnowSQL installed on your system.
Note: These instructions are meant to work for Windows, but are very similar for people working on Mac and Linux operating systems.
Start with forking this and creating your own repo on GitHub.
Add Miniconda scripts path to your environment variables system path (similar to C:\Users\kbasu\AppData\Local\miniconda3\Scripts ).
Create a root folder and point the VS Code to that directory using the command prompt terminal.
Clone your forked repository to the root directory. ( git clone <your project repo> ).
Move inside sfguide-data-engineering-with-snowpark-python ( cd sfguide-data-engineering-with-snowpark-python ).
Create conda environment ( conda env create -f environment.yml ). You should find environment.yml already present inside the root folder.
Activate the conda environment. ( conda activate snowflake-demo ).
Now you should see the new environment activated!
Here is what the project directory should look like:
Typically you’d want to create a separate folder structure for functions so that they can be deployed as is (no dependency):
An app.py – This is the main function where you will code. The file name can be different, but for standardization purposes, it is advised to use app.py.
An app.toml – This will help in deploying the code (we’ll share the formats for each of these files in the end).
A requirement.txt – Like any other Python project, this will be looked upon to find and install any specific Python library required for this particular functionality (for this particular UDF, it is kept blank as no additional library is required).
A .gitignore – This is automatically updated during git push and pull.
Main function – A simple multiplication function:
TOML file – App.zip will be automatically created while deploying the code, will come to that shortly. The rest should be self-explanatory.
Requirement file – Leave blank.
Git ignore file
Install the additional libraries (only for this new functionality) if required. We don’t have any in our example, but for reference, this is how you’d perform this:
Let’s test this function locally once (we need to be confident about the functionality of the newly added piece of code).
Now it’s time to deploy the code to Snowflake:
The deployment should be successful. In the next sections, we will review the deployment’s validation and the inner workings of the entire process.
Existence – The newly created Python UDF should be present under the Analytics schema under the HOL_DB database.
Content – Let’s validate the content. SnowCLI simplifies the process and automatically converts the Python code to SQL script (more on this in the next section).
Run the Function From Snowflake – Let’s test the functionality from Snowflake.
Test Locally – Now that we have tested the functionality from Snowflake, let’s test this from local.
In our example, the deployment worked just fine.
For Snowpark Python UDFs and sprocs in particular, the SnowCLI does all the heavy lifting of deploying the objects to Snowflake. Here is what it does in the background:
Dealing with third-party packages
For packages that can be accessed directly from our Anaconda environment, it will add them to the packages list in the create function SQL command.
For packages that are not currently available in our Anaconda environment, it will download the code and include them in the project zip file.
Creates a zip file of everything in your project, including the following:
Copying that project zip file to the Snowflake stage:
Creating the Snowflake function object:
More on SnowCLI can be found here since it is still being developed by Snowflake. For a comprehensive guide to writing Python UDF, check out this guide.
Next, we will deploy the changes back to git.
Configure Forked Repo – From the repository, follow this route – Settings > Secrets and variables > Actions > New repository secret near the top right and enter the names given below along with the appropriate values:
Configure SnowSQL Parameters: From the VS Code editor, press CTRL-P. Search for ~/.snowsql/config .
Configure similar to the above settings.
Push Your Changes and Commit
You should already see pending changes in your VS Code git source control section.
Enter a suitable message and commit.
If not added already, add your username and email ID as authorized credentials for git:
You can commit and then sync, or there’s an option to commit and sync.
Verify the success message and no pending changes in the source control section.
Verify the Changes on git
Go to the actions tab in GitHub and find the latest git workflow run.
Click on the latest run and verify the details.
In the latest codebase, verify that the latest changes are present.
Now you may ask, when is it the right time to go via the Snowpark route? Here are some of our best practices to follow:
If you have too few Python (or any other non-SQL programming language) UDFs to write/already written, you may want to go via the Python worksheet route instead.
If your data pipeline requirements are quite straightforward—i.e., they don’t have too many different conditional logics, too many different types of workloads, or changing requirements—and pipelines can be written in plain SQL without any foreseeing debugging issues, then you may not want to over-engineer and stick to traditional SQL-based Snowflake pipelines.
If you have a simple migration requirement (e.g., Hive tables must be migrated to Snowflake ), check if you can use Snowflake-Spark connectors directly instead of going via the Snowpark route.
Snowpark will have the greatest impact on the following use cases:
You have migration requirements with data cleansing/transformation/standardization logic written/not written in Spark.
You have different types of workloads to handle with varying requirements.
You have different developers working on building data pipelines/UDFs/stored procedures in the same environment.
You have code written in different languages(Java/Python etc.), and you want to have a common platform without having to worry about infrastructure considerations.
You already have an SQL-based data pipeline, but changing it to meet new requirements would require extensive changes.
You want a Spark-like programming environment.
Thank you so much for reading! Our hope is that this article helps you get the most out of Snowpark. If you need help, have questions, or want to learn more about how Snowpark & Snowflake can help your business make more informed decisions, the experts at phData can help!
As Snowflake’s 2024 Partner of the Year , phData can confidently help you get the most out of your Snowflake investment. Explore our Snowflake services today, especially our Snowpark MVP program.
When you use the Snowflake Python connector, you are fetching the data from Snowflake and bringing it to the compute instance(the public cloud you are using- AWS/Azure/GCP) where your Python code is running for further processing. In Snowpark, your Python (Or Scala/Java) program(for data processing), which is coded as a UDF runs on the snowflake engine(using SnowCLI connecting to a virtual warehouse) itself. So, you do not need to bring the data out of Snowflake for processing, thus making it a better choice if you’re concerned about security. In addition to this, there are the following benefits of using Snowpark instead-
Support for interacting with data within Snowflake using libraries and patterns purpose built for different languages without compromising on performance or functionality.
Support for authoring Snowpark code using local tools such as Jupyter, VS Code, or IntelliJ.
Support for pushdown for all operations, including Snowflake UDFs. This means Snowpark pushes down all data transformation and heavy lifting to the Snowflake data cloud, enabling you to efficiently work with data of any size.
By now, you must already know that Snowpark requires the users/developers to be comfortable with at least 1 programming language. Here are some additional points-
Snowpark is a relatively new technology, and some bugs or performance issues may not yet have been identified.
Snowpark is a programming model, and it requires some level of programming expertise to use.
Snowpark is not currently available for all Snowflake regions.
There are some limitations around stored procedure in writing .
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A Python lehetővé teszi a zip/tar gyors létrehozását archilátod.
Following parancs a teljes könyvtárat tömöríti
Following parancs segítségével szabályozhatja a kívánt fájlokat archive
Íme a lépések a ZIP-fájl létrehozásához a Pythonban
Step 1) Annak létrehozásához archive fájlt Pythonból, győződjön meg arról, hogy az importálási nyilatkozat helyes és rendben van. Itt az import nyilatkozat a archive is from shutil import make_archive
Kód Magyarázat
Step 2) Miután a archive fájl elkészült, kattintson a jobb gombbal a fájlra, és válassza ki az operációs rendszert, és megjelenik az Ön archive fájlokat az alábbiak szerint
Most a archiA ve.zip fájl megjelenik az operációs rendszerén (Windows Explorer)
Step 3) Amikor double-kattintson a fájlra, látni fogja az ott lévő összes fájl listáját.
Step 4) Pythonban jobban irányíthatjuk archive mivel meg tudjuk határozni, hogy melyik fájlba kerüljön bele archive. A mi esetünkben két fájlt mellékelünk alá archive "guru99.txt" és a „guru99.txt.bak”.
Amikor végrehajtja a kódot, láthatja, hogy a panel jobb oldalán létrejön a fájl „guru99.zip” néven.
Megjegyzések : Itt nem adunk parancsot a fájl „bezárására”, mint például a „newzip.close”, mert „With” hatókör zárolást használunk, így ha a program ezen a hatókörön kívül esik, a fájl megtisztul és automatikusan bezárul.
Step 5) Amikor -> kattintson jobb gombbal a fájlra (testguru99.zip), és -> válassza ki az operációs rendszert (Windows Explorer) , megmutatja a archive fájlokat a mappában az alábbiak szerint.
Amikor double kattintson a „testguru99.zip” fájlra, megnyílik egy másik ablak, és ez mutatja a benne található fájlokat.
Itt a teljes kód
Python 2 példa
Python 3 példa
在日常数据处理和文件管理中,压缩文件是一种常见的文件格式。使用Python可以方便地自动化处理压缩文件,包括压缩和解压各种格式的文件,如ZIP、TAR、GZ等。本文将详细介绍如何使用Python处理这些压缩文件,涵盖基本操作、常用库及其应用场景,并提供相应的示例代码。
zipfile 模块是Python内置的用于处理ZIP文件的模块,支持创建、读取、写入和解压ZIP文件。
使用 zipfile 模块可以方便地读取ZIP文件中的内容。
可以使用 zipfile 模块创建新的ZIP文件,并向其中添加文件。
可以使用 zipfile 模块向现有的ZIP文件中添加文件。
tarfile 模块是Python内置的用于处理TAR文件的模块,支持创建、读取、写入和解压TAR文件。
使用 tarfile 模块可以方便地读取TAR文件中的内容。
可以使用 tarfile 模块创建新的TAR文件,并向其中添加文件。
可以使用 tarfile 模块向现有的TAR文件中添加文件。
shutil 模块提供了高级的文件操作功能,包括对压缩文件的处理,支持创建和解压ZIP和TAR格式的文件。
使用 shutil 模块可以方便地创建压缩文件。
使用 shutil 模块可以方便地解压压缩文件。
下面是一个自动备份文件夹的示例,使用 zipfile 模块将指定文件夹压缩为ZIP文件,并保存到指定位置。
下面是一个自动解压ZIP文件并处理其中文件的示例,解压后对每个文件进行简单处理(如打印文件内容)。
本文详细介绍了如何使用Python自动化处理压缩文件,包括读取、创建、添加和解压ZIP和TAR文件。通过使用Python内置的 zipfile 、 tarfile 和 shutil 模块,开发者可以高效地管理压缩文件,实现自动化文件处理。文中提供了丰富的示例代码,展示了如何在实际应用中使用这些模块进行文件备份和解压操作。掌握这些技术,不仅可以提高工作效率,还能简化日常文件管理任务。
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Source code: Lib/sqlite3/
SQLite is a C library that provides a lightweight disk-based database that doesn’t require a separate server process and allows accessing the database using a nonstandard variant of the SQL query language. Some applications can use SQLite for internal data storage. It’s also possible to prototype an application using SQLite and then port the code to a larger database such as PostgreSQL or Oracle.
The sqlite3 module was written by Gerhard Häring. It provides an SQL interface compliant with the DB-API 2.0 specification described by PEP 249 , and requires SQLite 3.15.2 or newer.
This document includes four main sections:
Tutorial teaches how to use the sqlite3 module.
Reference describes the classes and functions this module defines.
How-to guides details how to handle specific tasks.
Explanation provides in-depth background on transaction control.
The SQLite web page; the documentation describes the syntax and the available data types for the supported SQL dialect.
Tutorial, reference and examples for learning SQL syntax.
PEP written by Marc-André Lemburg.
In this tutorial, you will create a database of Monty Python movies using basic sqlite3 functionality. It assumes a fundamental understanding of database concepts, including cursors and transactions .
First, we need to create a new database and open a database connection to allow sqlite3 to work with it. Call sqlite3.connect() to create a connection to the database tutorial.db in the current working directory, implicitly creating it if it does not exist:
The returned Connection object con represents the connection to the on-disk database.
In order to execute SQL statements and fetch results from SQL queries, we will need to use a database cursor. Call con.cursor() to create the Cursor :
Now that we’ve got a database connection and a cursor, we can create a database table movie with columns for title, release year, and review score. For simplicity, we can just use column names in the table declaration – thanks to the flexible typing feature of SQLite, specifying the data types is optional. Execute the CREATE TABLE statement by calling cur.execute(...) :
We can verify that the new table has been created by querying the sqlite_master table built-in to SQLite, which should now contain an entry for the movie table definition (see The Schema Table for details). Execute that query by calling cur.execute(...) , assign the result to res , and call res.fetchone() to fetch the resulting row:
We can see that the table has been created, as the query returns a tuple containing the table’s name. If we query sqlite_master for a non-existent table spam , res.fetchone() will return None :
Now, add two rows of data supplied as SQL literals by executing an INSERT statement, once again by calling cur.execute(...) :
The INSERT statement implicitly opens a transaction, which needs to be committed before changes are saved in the database (see Transaction control for details). Call con.commit() on the connection object to commit the transaction:
We can verify that the data was inserted correctly by executing a SELECT query. Use the now-familiar cur.execute(...) to assign the result to res , and call res.fetchall() to return all resulting rows:
The result is a list of two tuple s, one per row, each containing that row’s score value.
Now, insert three more rows by calling cur.executemany(...) :
Notice that ? placeholders are used to bind data to the query. Always use placeholders instead of string formatting to bind Python values to SQL statements, to avoid SQL injection attacks (see How to use placeholders to bind values in SQL queries for more details).
We can verify that the new rows were inserted by executing a SELECT query, this time iterating over the results of the query:
Each row is a two-item tuple of (year, title) , matching the columns selected in the query.
Finally, verify that the database has been written to disk by calling con.close() to close the existing connection, opening a new one, creating a new cursor, then querying the database:
You’ve now created an SQLite database using the sqlite3 module, inserted data and retrieved values from it in multiple ways.
How-to guides for further reading:
How to adapt custom Python types to SQLite values
Explanation for in-depth background on transaction control.
Module functions ¶.
Open a connection to an SQLite database.
database ( path-like object ) – The path to the database file to be opened. You can pass ":memory:" to create an SQLite database existing only in memory , and open a connection to it.
timeout ( float ) – How many seconds the connection should wait before raising an OperationalError when a table is locked. If another connection opens a transaction to modify a table, that table will be locked until the transaction is committed. Default five seconds.
detect_types ( int ) – Control whether and how data types not natively supported by SQLite are looked up to be converted to Python types, using the converters registered with register_converter() . Set it to any combination (using | , bitwise or) of PARSE_DECLTYPES and PARSE_COLNAMES to enable this. Column names takes precedence over declared types if both flags are set. Types cannot be detected for generated fields (for example max(data) ), even when the detect_types parameter is set; str will be returned instead. By default ( 0 ), type detection is disabled.
isolation_level ( str | None ) – Control legacy transaction handling behaviour. See Connection.isolation_level and Transaction control via the isolation_level attribute for more information. Can be "DEFERRED" (default), "EXCLUSIVE" or "IMMEDIATE" ; or None to disable opening transactions implicitly. Has no effect unless Connection.autocommit is set to LEGACY_TRANSACTION_CONTROL (the default).
check_same_thread ( bool ) – If True (default), ProgrammingError will be raised if the database connection is used by a thread other than the one that created it. If False , the connection may be accessed in multiple threads; write operations may need to be serialized by the user to avoid data corruption. See threadsafety for more information.
factory ( Connection ) – A custom subclass of Connection to create the connection with, if not the default Connection class.
cached_statements ( int ) – The number of statements that sqlite3 should internally cache for this connection, to avoid parsing overhead. By default, 128 statements.
uri ( bool ) – If set to True , database is interpreted as a URI with a file path and an optional query string. The scheme part must be "file:" , and the path can be relative or absolute. The query string allows passing parameters to SQLite, enabling various How to work with SQLite URIs .
autocommit ( bool ) – Control PEP 249 transaction handling behaviour. See Connection.autocommit and Transaction control via the autocommit attribute for more information. autocommit currently defaults to LEGACY_TRANSACTION_CONTROL . The default will change to False in a future Python release.
Raises an auditing event sqlite3.connect with argument database .
Raises an auditing event sqlite3.connect/handle with argument connection_handle .
Cambiato nella versione 3.4: Added the uri parameter.
Cambiato nella versione 3.7: database can now also be a path-like object , not only a string.
Cambiato nella versione 3.10: Added the sqlite3.connect/handle auditing event.
Cambiato nella versione 3.12: Added the autocommit parameter.
Cambiato nella versione 3.13: Positional use of the parameters timeout , detect_types , isolation_level , check_same_thread , factory , cached_statements , and uri is deprecated. They will become keyword-only parameters in Python 3.15.
Return True if the string statement appears to contain one or more complete SQL statements. No syntactic verification or parsing of any kind is performed, other than checking that there are no unclosed string literals and the statement is terminated by a semicolon.
For example:
This function may be useful during command-line input to determine if the entered text seems to form a complete SQL statement, or if additional input is needed before calling execute() .
See runsource() in Lib/sqlite3/__main__.py for real-world use.
Enable or disable callback tracebacks. By default you will not get any tracebacks in user-defined functions, aggregates, converters, authorizer callbacks etc. If you want to debug them, you can call this function with flag set to True . Afterwards, you will get tracebacks from callbacks on sys.stderr . Use False to disable the feature again.
Errors in user-defined function callbacks are logged as unraisable exceptions. Use an unraisable hook handler for introspection of the failed callback.
Register an adapter callable to adapt the Python type type into an SQLite type. The adapter is called with a Python object of type type as its sole argument, and must return a value of a type that SQLite natively understands .
Register the converter callable to convert SQLite objects of type typename into a Python object of a specific type. The converter is invoked for all SQLite values of type typename ; it is passed a bytes object and should return an object of the desired Python type. Consult the parameter detect_types of connect() for information regarding how type detection works.
Note: typename and the name of the type in your query are matched case-insensitively.
Set autocommit to this constant to select old style (pre-Python 3.12) transaction control behaviour. See Transaction control via the isolation_level attribute for more information.
Pass this flag value to the detect_types parameter of connect() to look up a converter function by using the type name, parsed from the query column name, as the converter dictionary key. The type name must be wrapped in square brackets ( [] ).
This flag may be combined with PARSE_DECLTYPES using the | (bitwise or) operator.
Pass this flag value to the detect_types parameter of connect() to look up a converter function using the declared types for each column. The types are declared when the database table is created. sqlite3 will look up a converter function using the first word of the declared type as the converter dictionary key. For example:
This flag may be combined with PARSE_COLNAMES using the | (bitwise or) operator.
Flags that should be returned by the authorizer_callback callable passed to Connection.set_authorizer() , to indicate whether:
Access is allowed ( SQLITE_OK ),
The SQL statement should be aborted with an error ( SQLITE_DENY )
The column should be treated as a NULL value ( SQLITE_IGNORE )
String constant stating the supported DB-API level. Required by the DB-API. Hard-coded to "2.0" .
String constant stating the type of parameter marker formatting expected by the sqlite3 module. Required by the DB-API. Hard-coded to "qmark" .
The named DB-API parameter style is also supported.
Version number of the runtime SQLite library as a string .
Version number of the runtime SQLite library as a tuple of integers .
Integer constant required by the DB-API 2.0, stating the level of thread safety the sqlite3 module supports. This attribute is set based on the default threading mode the underlying SQLite library is compiled with. The SQLite threading modes are:
Single-thread : In this mode, all mutexes are disabled and SQLite is unsafe to use in more than a single thread at once.
Multi-thread : In this mode, SQLite can be safely used by multiple threads provided that no single database connection is used simultaneously in two or more threads.
Serialized : In serialized mode, SQLite can be safely used by multiple threads with no restriction.
The mappings from SQLite threading modes to DB-API 2.0 threadsafety levels are as follows:
SQLite threading mode |
|
| DB-API 2.0 meaning |
---|---|---|---|
single-thread | 0 | 0 | Threads may not share the module |
multi-thread | 1 | 2 | Threads may share the module, but not connections |
serialized | 3 | 1 | Threads may share the module, connections and cursors |
Cambiato nella versione 3.11: Set threadsafety dynamically instead of hard-coding it to 1 .
These constants are used for the Connection.setconfig() and getconfig() methods.
The availability of these constants varies depending on the version of SQLite Python was compiled with.
Added in version 3.12.
SQLite docs: Database Connection Configuration Options
Deprecato dalla versione 3.12, rimosso nella versione 3.14.: The version and version_info constants.
Each open SQLite database is represented by a Connection object, which is created using sqlite3.connect() . Their main purpose is creating Cursor objects, and Transaction control .
Cambiato nella versione 3.13: A ResourceWarning is emitted if close() is not called before a Connection object is deleted.
An SQLite database connection has the following attributes and methods:
Create and return a Cursor object. The cursor method accepts a single optional parameter factory . If supplied, this must be a callable returning an instance of Cursor or its subclasses.
Open a Blob handle to an existing BLOB .
table ( str ) – The name of the table where the blob is located.
column ( str ) – The name of the column where the blob is located.
row ( str ) – The name of the row where the blob is located.
readonly ( bool ) – Set to True if the blob should be opened without write permissions. Defaults to False .
name ( str ) – The name of the database where the blob is located. Defaults to "main" .
OperationalError – When trying to open a blob in a WITHOUT ROWID table.
The blob size cannot be changed using the Blob class. Use the SQL function zeroblob to create a blob with a fixed size.
Added in version 3.11.
Commit any pending transaction to the database. If autocommit is True , or there is no open transaction, this method does nothing. If autocommit is False , a new transaction is implicitly opened if a pending transaction was committed by this method.
Roll back to the start of any pending transaction. If autocommit is True , or there is no open transaction, this method does nothing. If autocommit is False , a new transaction is implicitly opened if a pending transaction was rolled back by this method.
Close the database connection. If autocommit is False , any pending transaction is implicitly rolled back. If autocommit is True or LEGACY_TRANSACTION_CONTROL , no implicit transaction control is executed. Make sure to commit() before closing to avoid losing pending changes.
Create a new Cursor object and call execute() on it with the given sql and parameters . Return the new cursor object.
Create a new Cursor object and call executemany() on it with the given sql and parameters . Return the new cursor object.
Create a new Cursor object and call executescript() on it with the given sql_script . Return the new cursor object.
Create or remove a user-defined SQL function.
name ( str ) – The name of the SQL function.
narg ( int ) – The number of arguments the SQL function can accept. If -1 , it may take any number of arguments.
func ( callback | None) – A callable that is called when the SQL function is invoked. The callable must return a type natively supported by SQLite . Set to None to remove an existing SQL function.
deterministic ( bool ) – If True , the created SQL function is marked as deterministic , which allows SQLite to perform additional optimizations.
Cambiato nella versione 3.8: Added the deterministic parameter.
Cambiato nella versione 3.13: Passing name , narg , and func as keyword arguments is deprecated. These parameters will become positional-only in Python 3.15.
Create or remove a user-defined SQL aggregate function.
name ( str ) – The name of the SQL aggregate function.
n_arg ( int ) – The number of arguments the SQL aggregate function can accept. If -1 , it may take any number of arguments.
A class must implement the following methods:
step() : Add a row to the aggregate.
finalize() : Return the final result of the aggregate as a type natively supported by SQLite .
The number of arguments that the step() method must accept is controlled by n_arg .
Set to None to remove an existing SQL aggregate function.
Cambiato nella versione 3.13: Passing name , n_arg , and aggregate_class as keyword arguments is deprecated. These parameters will become positional-only in Python 3.15.
Create or remove a user-defined aggregate window function.
name ( str ) – The name of the SQL aggregate window function to create or remove.
num_params ( int ) – The number of arguments the SQL aggregate window function can accept. If -1 , it may take any number of arguments.
A class that must implement the following methods:
step() : Add a row to the current window.
value() : Return the current value of the aggregate.
inverse() : Remove a row from the current window.
The number of arguments that the step() and value() methods must accept is controlled by num_params .
Set to None to remove an existing SQL aggregate window function.
NotSupportedError – If used with a version of SQLite older than 3.25.0, which does not support aggregate window functions.
Create a collation named name using the collating function callable . callable is passed two string arguments, and it should return an integer :
1 if the first is ordered higher than the second
-1 if the first is ordered lower than the second
0 if they are ordered equal
The following example shows a reverse sorting collation:
Remove a collation function by setting callable to None .
Cambiato nella versione 3.11: The collation name can contain any Unicode character. Earlier, only ASCII characters were allowed.
Call this method from a different thread to abort any queries that might be executing on the connection. Aborted queries will raise an OperationalError .
Register callable authorizer_callback to be invoked for each attempt to access a column of a table in the database. The callback should return one of SQLITE_OK , SQLITE_DENY , or SQLITE_IGNORE to signal how access to the column should be handled by the underlying SQLite library.
The first argument to the callback signifies what kind of operation is to be authorized. The second and third argument will be arguments or None depending on the first argument. The 4th argument is the name of the database («main», «temp», etc.) if applicable. The 5th argument is the name of the inner-most trigger or view that is responsible for the access attempt or None if this access attempt is directly from input SQL code.
Please consult the SQLite documentation about the possible values for the first argument and the meaning of the second and third argument depending on the first one. All necessary constants are available in the sqlite3 module.
Passing None as authorizer_callback will disable the authorizer.
Cambiato nella versione 3.11: Added support for disabling the authorizer using None .
Cambiato nella versione 3.13: Passing authorizer_callback as a keyword argument is deprecated. The parameter will become positional-only in Python 3.15.
Register callable progress_handler to be invoked for every n instructions of the SQLite virtual machine. This is useful if you want to get called from SQLite during long-running operations, for example to update a GUI.
If you want to clear any previously installed progress handler, call the method with None for progress_handler .
Returning a non-zero value from the handler function will terminate the currently executing query and cause it to raise a DatabaseError exception.
Cambiato nella versione 3.13: Passing progress_handler as a keyword argument is deprecated. The parameter will become positional-only in Python 3.15.
Register callable trace_callback to be invoked for each SQL statement that is actually executed by the SQLite backend.
The only argument passed to the callback is the statement (as str ) that is being executed. The return value of the callback is ignored. Note that the backend does not only run statements passed to the Cursor.execute() methods. Other sources include the transaction management of the sqlite3 module and the execution of triggers defined in the current database.
Passing None as trace_callback will disable the trace callback.
Exceptions raised in the trace callback are not propagated. As a development and debugging aid, use enable_callback_tracebacks() to enable printing tracebacks from exceptions raised in the trace callback.
Added in version 3.3.
Cambiato nella versione 3.13: Passing trace_callback as a keyword argument is deprecated. The parameter will become positional-only in Python 3.15.
Enable the SQLite engine to load SQLite extensions from shared libraries if enabled is True ; else, disallow loading SQLite extensions. SQLite extensions can define new functions, aggregates or whole new virtual table implementations. One well-known extension is the fulltext-search extension distributed with SQLite.
The sqlite3 module is not built with loadable extension support by default, because some platforms (notably macOS) have SQLite libraries which are compiled without this feature. To get loadable extension support, you must pass the --enable-loadable-sqlite-extensions option to configure .
Raises an auditing event sqlite3.enable_load_extension with arguments connection , enabled .
Added in version 3.2.
Cambiato nella versione 3.10: Added the sqlite3.enable_load_extension auditing event.
Load an SQLite extension from a shared library. Enable extension loading with enable_load_extension() before calling this method.
path ( str ) – The path to the SQLite extension.
entrypoint ( str | None ) – Entry point name. If None (the default), SQLite will come up with an entry point name of its own; see the SQLite docs Loading an Extension for details.
Raises an auditing event sqlite3.load_extension with arguments connection , path .
Cambiato nella versione 3.10: Added the sqlite3.load_extension auditing event.
Cambiato nella versione 3.12: Added the entrypoint parameter.
Return an iterator to dump the database as SQL source code. Useful when saving an in-memory database for later restoration. Similar to the .dump command in the sqlite3 shell.
filter ( str | None ) – An optional LIKE pattern for database objects to dump, e.g. prefix_% . If None (the default), all database objects will be included.
Cambiato nella versione 3.13: Added the filter parameter.
Create a backup of an SQLite database.
Works even if the database is being accessed by other clients or concurrently by the same connection.
target ( Connection ) – The database connection to save the backup to.
pages ( int ) – The number of pages to copy at a time. If equal to or less than 0 , the entire database is copied in a single step. Defaults to -1 .
progress ( callback | None) – If set to a callable , it is invoked with three integer arguments for every backup iteration: the status of the last iteration, the remaining number of pages still to be copied, and the total number of pages. Defaults to None .
name ( str ) – The name of the database to back up. Either "main" (the default) for the main database, "temp" for the temporary database, or the name of a custom database as attached using the ATTACH DATABASE SQL statement.
sleep ( float ) – The number of seconds to sleep between successive attempts to back up remaining pages.
Example 1, copy an existing database into another:
Example 2, copy an existing database into a transient copy:
Added in version 3.7.
Get a connection runtime limit.
category ( int ) – The SQLite limit category to be queried.
ProgrammingError – If category is not recognised by the underlying SQLite library.
Example, query the maximum length of an SQL statement for Connection con (the default is 1000000000):
Set a connection runtime limit. Attempts to increase a limit above its hard upper bound are silently truncated to the hard upper bound. Regardless of whether or not the limit was changed, the prior value of the limit is returned.
category ( int ) – The SQLite limit category to be set.
limit ( int ) – The value of the new limit. If negative, the current limit is unchanged.
Example, limit the number of attached databases to 1 for Connection con (the default limit is 10):
Query a boolean connection configuration option.
op ( int ) – A SQLITE_DBCONFIG code .
Set a boolean connection configuration option.
enable ( bool ) – True if the configuration option should be enabled (default); False if it should be disabled.
Serialize a database into a bytes object. For an ordinary on-disk database file, the serialization is just a copy of the disk file. For an in-memory database or a «temp» database, the serialization is the same sequence of bytes which would be written to disk if that database were backed up to disk.
name ( str ) – The database name to be serialized. Defaults to "main" .
This method is only available if the underlying SQLite library has the serialize API.
Deserialize a serialized database into a Connection . This method causes the database connection to disconnect from database name , and reopen name as an in-memory database based on the serialization contained in data .
data ( bytes ) – A serialized database.
name ( str ) – The database name to deserialize into. Defaults to "main" .
OperationalError – If the database connection is currently involved in a read transaction or a backup operation.
DatabaseError – If data does not contain a valid SQLite database.
OverflowError – If len(data) is larger than 2**63 - 1 .
This method is only available if the underlying SQLite library has the deserialize API.
This attribute controls PEP 249 -compliant transaction behaviour. autocommit has three allowed values:
False : Select PEP 249 -compliant transaction behaviour, implying that sqlite3 ensures a transaction is always open. Use commit() and rollback() to close transactions.
This is the recommended value of autocommit .
True : Use SQLite’s autocommit mode . commit() and rollback() have no effect in this mode.
LEGACY_TRANSACTION_CONTROL : Pre-Python 3.12 (non- PEP 249 -compliant) transaction control. See isolation_level for more details.
This is currently the default value of autocommit .
Changing autocommit to False will open a new transaction, and changing it to True will commit any pending transaction.
See Transaction control via the autocommit attribute for more details.
The isolation_level attribute has no effect unless autocommit is LEGACY_TRANSACTION_CONTROL .
This read-only attribute corresponds to the low-level SQLite autocommit mode .
True if a transaction is active (there are uncommitted changes), False otherwise.
Controls the legacy transaction handling mode of sqlite3 . If set to None , transactions are never implicitly opened. If set to one of "DEFERRED" , "IMMEDIATE" , or "EXCLUSIVE" , corresponding to the underlying SQLite transaction behaviour , implicit transaction management is performed.
If not overridden by the isolation_level parameter of connect() , the default is "" , which is an alias for "DEFERRED" .
Using autocommit to control transaction handling is recommended over using isolation_level . isolation_level has no effect unless autocommit is set to LEGACY_TRANSACTION_CONTROL (the default).
The initial row_factory for Cursor objects created from this connection. Assigning to this attribute does not affect the row_factory of existing cursors belonging to this connection, only new ones. Is None by default, meaning each row is returned as a tuple .
See How to create and use row factories for more details.
A callable that accepts a bytes parameter and returns a text representation of it. The callable is invoked for SQLite values with the TEXT data type. By default, this attribute is set to str .
See How to handle non-UTF-8 text encodings for more details.
Return the total number of database rows that have been modified, inserted, or deleted since the database connection was opened.
A Cursor object represents a database cursor which is used to execute SQL statements, and manage the context of a fetch operation. Cursors are created using Connection.cursor() , or by using any of the connection shortcut methods . Cursor objects are iterators , meaning that if you execute() a SELECT query, you can simply iterate over the cursor to fetch the resulting rows: for row in cur . execute ( "SELECT t FROM data" ): print ( row )
A Cursor instance has the following attributes and methods.
Execute a single SQL statement, optionally binding Python values using placeholders .
sql ( str ) – A single SQL statement.
parameters ( dict | sequence ) – Python values to bind to placeholders in sql . A dict if named placeholders are used. A sequence if unnamed placeholders are used. See How to use placeholders to bind values in SQL queries .
ProgrammingError – If sql contains more than one SQL statement.
If autocommit is LEGACY_TRANSACTION_CONTROL , isolation_level is not None , sql is an INSERT , UPDATE , DELETE , or REPLACE statement, and there is no open transaction, a transaction is implicitly opened before executing sql .
Deprecato dalla versione 3.12, rimosso nella versione 3.14.: DeprecationWarning is emitted if named placeholders are used and parameters is a sequence instead of a dict . Starting with Python 3.14, ProgrammingError will be raised instead.
Use executescript() to execute multiple SQL statements.
For every item in parameters , repeatedly execute the parameterized DML SQL statement sql .
Uses the same implicit transaction handling as execute() .
sql ( str ) – A single SQL DML statement.
parameters ( iterable ) – An iterable of parameters to bind with the placeholders in sql . See How to use placeholders to bind values in SQL queries .
ProgrammingError – If sql contains more than one SQL statement, or is not a DML statement.
Any resulting rows are discarded, including DML statements with RETURNING clauses .
Deprecato dalla versione 3.12, rimosso nella versione 3.14.: DeprecationWarning is emitted if named placeholders are used and the items in parameters are sequences instead of dict s. Starting with Python 3.14, ProgrammingError will be raised instead.
Execute the SQL statements in sql_script . If the autocommit is LEGACY_TRANSACTION_CONTROL and there is a pending transaction, an implicit COMMIT statement is executed first. No other implicit transaction control is performed; any transaction control must be added to sql_script .
sql_script must be a string .
If row_factory is None , return the next row query result set as a tuple . Else, pass it to the row factory and return its result. Return None if no more data is available.
Return the next set of rows of a query result as a list . Return an empty list if no more rows are available.
The number of rows to fetch per call is specified by the size parameter. If size is not given, arraysize determines the number of rows to be fetched. If fewer than size rows are available, as many rows as are available are returned.
Note there are performance considerations involved with the size parameter. For optimal performance, it is usually best to use the arraysize attribute. If the size parameter is used, then it is best for it to retain the same value from one fetchmany() call to the next.
Return all (remaining) rows of a query result as a list . Return an empty list if no rows are available. Note that the arraysize attribute can affect the performance of this operation.
Close the cursor now (rather than whenever __del__ is called).
The cursor will be unusable from this point forward; a ProgrammingError exception will be raised if any operation is attempted with the cursor.
Required by the DB-API. Does nothing in sqlite3 .
Read/write attribute that controls the number of rows returned by fetchmany() . The default value is 1 which means a single row would be fetched per call.
Read-only attribute that provides the SQLite database Connection belonging to the cursor. A Cursor object created by calling con.cursor() will have a connection attribute that refers to con :
Read-only attribute that provides the column names of the last query. To remain compatible with the Python DB API, it returns a 7-tuple for each column where the last six items of each tuple are None .
It is set for SELECT statements without any matching rows as well.
Read-only attribute that provides the row id of the last inserted row. It is only updated after successful INSERT or REPLACE statements using the execute() method. For other statements, after executemany() or executescript() , or if the insertion failed, the value of lastrowid is left unchanged. The initial value of lastrowid is None .
Inserts into WITHOUT ROWID tables are not recorded.
Cambiato nella versione 3.6: Added support for the REPLACE statement.
Read-only attribute that provides the number of modified rows for INSERT , UPDATE , DELETE , and REPLACE statements; is -1 for other statements, including CTE queries. It is only updated by the execute() and executemany() methods, after the statement has run to completion. This means that any resulting rows must be fetched in order for rowcount to be updated.
Control how a row fetched from this Cursor is represented. If None , a row is represented as a tuple . Can be set to the included sqlite3.Row ; or a callable that accepts two arguments, a Cursor object and the tuple of row values, and returns a custom object representing an SQLite row.
Defaults to what Connection.row_factory was set to when the Cursor was created. Assigning to this attribute does not affect Connection.row_factory of the parent connection.
A Row instance serves as a highly optimized row_factory for Connection objects. It supports iteration, equality testing, len() , and mapping access by column name and index.
Two Row objects compare equal if they have identical column names and values.
Return a list of column names as strings . Immediately after a query, it is the first member of each tuple in Cursor.description .
Cambiato nella versione 3.5: Added support of slicing.
A Blob instance is a file-like object that can read and write data in an SQLite BLOB . Call len(blob) to get the size (number of bytes) of the blob. Use indices and slices for direct access to the blob data.
Use the Blob as a context manager to ensure that the blob handle is closed after use.
Close the blob.
The blob will be unusable from this point onward. An Error (or subclass) exception will be raised if any further operation is attempted with the blob.
Read length bytes of data from the blob at the current offset position. If the end of the blob is reached, the data up to EOF will be returned. When length is not specified, or is negative, read() will read until the end of the blob.
Write data to the blob at the current offset. This function cannot change the blob length. Writing beyond the end of the blob will raise ValueError .
Return the current access position of the blob.
Set the current access position of the blob to offset . The origin argument defaults to os.SEEK_SET (absolute blob positioning). Other values for origin are os.SEEK_CUR (seek relative to the current position) and os.SEEK_END (seek relative to the blob’s end).
The PrepareProtocol type’s single purpose is to act as a PEP 246 style adaption protocol for objects that can adapt themselves to native SQLite types .
The exception hierarchy is defined by the DB-API 2.0 ( PEP 249 ).
This exception is not currently raised by the sqlite3 module, but may be raised by applications using sqlite3 , for example if a user-defined function truncates data while inserting. Warning is a subclass of Exception .
The base class of the other exceptions in this module. Use this to catch all errors with one single except statement. Error is a subclass of Exception .
If the exception originated from within the SQLite library, the following two attributes are added to the exception:
The numeric error code from the SQLite API
The symbolic name of the numeric error code from the SQLite API
Exception raised for misuse of the low-level SQLite C API. In other words, if this exception is raised, it probably indicates a bug in the sqlite3 module. InterfaceError is a subclass of Error .
Exception raised for errors that are related to the database. This serves as the base exception for several types of database errors. It is only raised implicitly through the specialised subclasses. DatabaseError is a subclass of Error .
Exception raised for errors caused by problems with the processed data, like numeric values out of range, and strings which are too long. DataError is a subclass of DatabaseError .
Exception raised for errors that are related to the database’s operation, and not necessarily under the control of the programmer. For example, the database path is not found, or a transaction could not be processed. OperationalError is a subclass of DatabaseError .
Exception raised when the relational integrity of the database is affected, e.g. a foreign key check fails. It is a subclass of DatabaseError .
Exception raised when SQLite encounters an internal error. If this is raised, it may indicate that there is a problem with the runtime SQLite library. InternalError is a subclass of DatabaseError .
Exception raised for sqlite3 API programming errors, for example supplying the wrong number of bindings to a query, or trying to operate on a closed Connection . ProgrammingError is a subclass of DatabaseError .
Exception raised in case a method or database API is not supported by the underlying SQLite library. For example, setting deterministic to True in create_function() , if the underlying SQLite library does not support deterministic functions. NotSupportedError is a subclass of DatabaseError .
SQLite natively supports the following types: NULL , INTEGER , REAL , TEXT , BLOB .
The following Python types can thus be sent to SQLite without any problem:
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The type system of the sqlite3 module is extensible in two ways: you can store additional Python types in an SQLite database via object adapters , and you can let the sqlite3 module convert SQLite types to Python types via converters .
The default adapters and converters are deprecated as of Python 3.12. Instead, use the Adapter and converter recipes and tailor them to your needs.
The deprecated default adapters and converters consist of:
An adapter for datetime.date objects to strings in ISO 8601 format.
An adapter for datetime.datetime objects to strings in ISO 8601 format.
A converter for declared «date» types to datetime.date objects.
A converter for declared «timestamp» types to datetime.datetime objects. Fractional parts will be truncated to 6 digits (microsecond precision).
The default «timestamp» converter ignores UTC offsets in the database and always returns a naive datetime.datetime object. To preserve UTC offsets in timestamps, either leave converters disabled, or register an offset-aware converter with register_converter() .
Deprecato dalla versione 3.12.
The sqlite3 module can be invoked as a script, using the interpreter’s -m switch, in order to provide a simple SQLite shell. The argument signature is as follows:
Type .quit or CTRL-D to exit the shell.
Print CLI help.
Print underlying SQLite library version.
How to use placeholders to bind values in sql queries ¶.
SQL operations usually need to use values from Python variables. However, beware of using Python’s string operations to assemble queries, as they are vulnerable to SQL injection attacks . For example, an attacker can simply close the single quote and inject OR TRUE to select all rows:
Instead, use the DB-API’s parameter substitution. To insert a variable into a query string, use a placeholder in the string, and substitute the actual values into the query by providing them as a tuple of values to the second argument of the cursor’s execute() method.
An SQL statement may use one of two kinds of placeholders: question marks (qmark style) or named placeholders (named style). For the qmark style, parameters must be a sequence whose length must match the number of placeholders, or a ProgrammingError is raised. For the named style, parameters must be an instance of a dict (or a subclass), which must contain keys for all named parameters; any extra items are ignored. Here’s an example of both styles:
PEP 249 numeric placeholders are not supported. If used, they will be interpreted as named placeholders.
SQLite supports only a limited set of data types natively. To store custom Python types in SQLite databases, adapt them to one of the Python types SQLite natively understands .
There are two ways to adapt Python objects to SQLite types: letting your object adapt itself, or using an adapter callable . The latter will take precedence above the former. For a library that exports a custom type, it may make sense to enable that type to adapt itself. As an application developer, it may make more sense to take direct control by registering custom adapter functions.
Suppose we have a Point class that represents a pair of coordinates, x and y , in a Cartesian coordinate system. The coordinate pair will be stored as a text string in the database, using a semicolon to separate the coordinates. This can be implemented by adding a __conform__(self, protocol) method which returns the adapted value. The object passed to protocol will be of type PrepareProtocol .
The other possibility is to create a function that converts the Python object to an SQLite-compatible type. This function can then be registered using register_adapter() .
Writing an adapter lets you convert from custom Python types to SQLite values. To be able to convert from SQLite values to custom Python types, we use converters .
Let’s go back to the Point class. We stored the x and y coordinates separated via semicolons as strings in SQLite.
First, we’ll define a converter function that accepts the string as a parameter and constructs a Point object from it.
Converter functions are always passed a bytes object, no matter the underlying SQLite data type.
We now need to tell sqlite3 when it should convert a given SQLite value. This is done when connecting to a database, using the detect_types parameter of connect() . There are three options:
Implicit: set detect_types to PARSE_DECLTYPES
Explicit: set detect_types to PARSE_COLNAMES
Both: set detect_types to sqlite3.PARSE_DECLTYPES | sqlite3.PARSE_COLNAMES . Column names take precedence over declared types.
The following example illustrates the implicit and explicit approaches:
This section shows recipes for common adapters and converters.
Using the execute() , executemany() , and executescript() methods of the Connection class, your code can be written more concisely because you don’t have to create the (often superfluous) Cursor objects explicitly. Instead, the Cursor objects are created implicitly and these shortcut methods return the cursor objects. This way, you can execute a SELECT statement and iterate over it directly using only a single call on the Connection object.
A Connection object can be used as a context manager that automatically commits or rolls back open transactions when leaving the body of the context manager. If the body of the with statement finishes without exceptions, the transaction is committed. If this commit fails, or if the body of the with statement raises an uncaught exception, the transaction is rolled back. If autocommit is False , a new transaction is implicitly opened after committing or rolling back.
If there is no open transaction upon leaving the body of the with statement, or if autocommit is True , the context manager does nothing.
The context manager neither implicitly opens a new transaction nor closes the connection. If you need a closing context manager, consider using contextlib.closing() .
Some useful URI tricks include:
Open a database in read-only mode:
Do not implicitly create a new database file if it does not already exist; will raise OperationalError if unable to create a new file:
Create a shared named in-memory database:
More information about this feature, including a list of parameters, can be found in the SQLite URI documentation .
By default, sqlite3 represents each row as a tuple . If a tuple does not suit your needs, you can use the sqlite3.Row class or a custom row_factory .
While row_factory exists as an attribute both on the Cursor and the Connection , it is recommended to set Connection.row_factory , so all cursors created from the connection will use the same row factory.
Row provides indexed and case-insensitive named access to columns, with minimal memory overhead and performance impact over a tuple . To use Row as a row factory, assign it to the row_factory attribute:
Queries now return Row objects:
The FROM clause can be omitted in the SELECT statement, as in the above example. In such cases, SQLite returns a single row with columns defined by expressions, e.g. literals, with the given aliases expr AS alias .
You can create a custom row_factory that returns each row as a dict , with column names mapped to values:
Using it, queries now return a dict instead of a tuple :
The following row factory returns a named tuple :
namedtuple_factory() can be used as follows:
With some adjustments, the above recipe can be adapted to use a dataclass , or any other custom class, instead of a namedtuple .
By default, sqlite3 uses str to adapt SQLite values with the TEXT data type. This works well for UTF-8 encoded text, but it might fail for other encodings and invalid UTF-8. You can use a custom text_factory to handle such cases.
Because of SQLite’s flexible typing , it is not uncommon to encounter table columns with the TEXT data type containing non-UTF-8 encodings, or even arbitrary data. To demonstrate, let’s assume we have a database with ISO-8859-2 (Latin-2) encoded text, for example a table of Czech-English dictionary entries. Assuming we now have a Connection instance con connected to this database, we can decode the Latin-2 encoded text using this text_factory :
For invalid UTF-8 or arbitrary data in stored in TEXT table columns, you can use the following technique, borrowed from the Unicode HOWTO :
The sqlite3 module API does not support strings containing surrogates.
Unicode HOWTO
Transaction control ¶.
sqlite3 offers multiple methods of controlling whether, when and how database transactions are opened and closed. Transaction control via the autocommit attribute is recommended, while Transaction control via the isolation_level attribute retains the pre-Python 3.12 behaviour.
The recommended way of controlling transaction behaviour is through the Connection.autocommit attribute, which should preferably be set using the autocommit parameter of connect() .
It is suggested to set autocommit to False , which implies PEP 249 -compliant transaction control. This means:
sqlite3 ensures that a transaction is always open, so connect() , Connection.commit() , and Connection.rollback() will implicitly open a new transaction (immediately after closing the pending one, for the latter two). sqlite3 uses BEGIN DEFERRED statements when opening transactions.
Transactions should be committed explicitly using commit() .
Transactions should be rolled back explicitly using rollback() .
An implicit rollback is performed if the database is close() -ed with pending changes.
Set autocommit to True to enable SQLite’s autocommit mode . In this mode, Connection.commit() and Connection.rollback() have no effect. Note that SQLite’s autocommit mode is distinct from the PEP 249 -compliant Connection.autocommit attribute; use Connection.in_transaction to query the low-level SQLite autocommit mode.
Set autocommit to LEGACY_TRANSACTION_CONTROL to leave transaction control behaviour to the Connection.isolation_level attribute. See Transaction control via the isolation_level attribute for more information.
The recommended way of controlling transactions is via the autocommit attribute. See Transaction control via the autocommit attribute .
If Connection.autocommit is set to LEGACY_TRANSACTION_CONTROL (the default), transaction behaviour is controlled using the Connection.isolation_level attribute. Otherwise, isolation_level has no effect.
If the connection attribute isolation_level is not None , new transactions are implicitly opened before execute() and executemany() executes INSERT , UPDATE , DELETE , or REPLACE statements; for other statements, no implicit transaction handling is performed. Use the commit() and rollback() methods to respectively commit and roll back pending transactions. You can choose the underlying SQLite transaction behaviour — that is, whether and what type of BEGIN statements sqlite3 implicitly executes – via the isolation_level attribute.
If isolation_level is set to None , no transactions are implicitly opened at all. This leaves the underlying SQLite library in autocommit mode , but also allows the user to perform their own transaction handling using explicit SQL statements. The underlying SQLite library autocommit mode can be queried using the in_transaction attribute.
The executescript() method implicitly commits any pending transaction before execution of the given SQL script, regardless of the value of isolation_level .
Cambiato nella versione 3.6: sqlite3 used to implicitly commit an open transaction before DDL statements. This is no longer the case.
Cambiato nella versione 3.12: The recommended way of controlling transactions is now via the autocommit attribute.
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Data Compression and Archiving
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Aim-bot based on AI for all FPS games
Folders and files.
Name | Name | |||
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408 Commits | ||||
Sunone aimbot.
Sunone Aimbot is an AI-powered aim bot for first-person shooter games. It leverages the YOLOv8 and YOLOv10 models, PyTorch, and various other tools to automatically target and aim at enemies within the game. The AI model in repository has been trained on more than 30,000 images from popular first-person shooter games like Warface, Destiny 2, Battlefield 2042, CS:GO, Fortnite, The Finals, CS2 and more.
Use it at your own risk, we do not guarantee that you may be blocked!
This application only works on Nvidia graphics cards. AMD support is testing. See AI_enable_AMD option. The recommended graphics card for starting and more productive and stable operation starts with the rtx 20 series.
The sunone aimbot has been tested on the following environment:.
Windows | 10 and 11(priority) |
---|---|
Python: | 3.11.6 |
CUDA: | 12.4 |
TensorRT: | 10.0.1 |
Ultralytics: | 8.2.48 |
GitHub AI Model: | 0.4.1 (YOLOv8) |
Boosty AI Model: | 0.5.7 (YOLOv10) |
The behavior of the aimbot can be configured via the config.ini file. Here are the available options:
I will post new models here .
This project is licensed under the MIT License. See LICENSE for details
Volumes are Unity Catalog objects that enable governance over non-tabular datasets. Volumes represent a logical volume of storage in a cloud object storage location. Volumes provide capabilities for accessing, storing, governing, and organizing files.
While tables provide governance over tabular datasets, volumes add governance over non-tabular datasets. You can use volumes to store and access files in any format, including structured, semi-structured, and unstructured data.
Databricks recommends using volumes to govern access to all non-tabular data. Like tables, volumes can be managed or external.
You cannot use volumes as a location for tables. Volumes are intended for path-based data access only. Use tables when you want to work with tabular data in Unity Catalog.
The following articles provide more information about working with volumes:
Create and manage volumes .
Manage files in volumes .
Explore storage and find data files .
Managed vs. external volumes .
What are the privileges for volumes? .
When you work with volumes, you must use a SQL warehouse or a cluster running Databricks Runtime 13.3 LTS or above, unless you are using Databricks UIs such as Catalog Explorer.
A managed volume is a Unity Catalog-governed storage volume created within the managed storage location of the containing schema. See Specify a managed storage location in Unity Catalog .
Managed volumes allow the creation of governed storage for working with files without the overhead of external locations and storage credentials. You do not need to specify a location when creating a managed volume, and all file access for data in managed volumes is through paths managed by Unity Catalog.
An external volume is a Unity Catalog-governed storage volume registered against a directory within an external location using Unity Catalog-governed storage credentials.
Unity Catalog does not manage the lifecycle and layout of the files in external volumes. When you drop an external volume, Unity Catalog does not delete the underlying data.
Volumes sit at the third level of the Unity Catalog three-level namespace ( catalog.schema.volume ):
The path to access volumes is the same whether you use Apache Spark, SQL, Python, or other languages and libraries. This differs from legacy access patterns for files in object storage bound to a Databricks workspace.
The path to access files in volumes uses the following format:
Databricks also supports an optional dbfs:/ scheme when working with Apache Spark, so the following path also works:
The sequence /<catalog>/<schema>/<volume> in the path corresponds to the three Unity Catalog object names associated with the file. These path elements are read-only and not directly writeable by users, meaning it is not possible to create or delete these directories using filesystem operations. They are automatically managed and kept in sync with the corresponding Unity Catalog entities.
You can also access data in external volumes using cloud storage URIs.
The following notebook demonstrates the basic SQL syntax to create and interact with Unity Catalog volumes.
Reserved paths for volumes.
Volumes introduces the following reserved paths used for accessing volumes:
dbfs:/Volumes
Paths are also reserved for potential typos for these paths from Apache Spark APIs and dbutils , including /volumes , /Volume , /volume , whether or not they are preceded by dbfs:/ . The path /dbfs/Volumes is also reserved, but cannot be used to access volumes.
Volumes are only supported on Databricks Runtime 13.3 LTS and above. In Databricks Runtime 12.2 LTS and below, operations against /Volumes paths might succeed, but can write data to ephemeral storage disks attached to compute clusters rather than persisting data to Unity Catalog volumes as expected.
If you have pre-existing data stored in a reserved path on the DBFS root, you can file a support ticket to gain temporary access to this data to move it to another location.
You must use Unity Catalog-enabled compute to interact with Unity Catalog volumes. Volumes do not support all workloads.
Volumes do not support dbutils.fs commands distributed to executors.
The following limitations apply:
In Databricks Runtime 14.3 LTS and above:
On single-user user clusters, you cannot access volumes from threads and subprocesses in Scala.
In Databricks Runtime 14.2 and below:
On compute configured with shared access mode, you can’t use UDFs to access volumes.
Both Python or Scala have access to FUSE from the driver but not from executors.
Scala code that performs I/O operations can run on the driver but not the executors.
On compute configured with single user access mode, there is no support for FUSE in Scala, Scala IO code accessing data using volume paths, or Scala UDFs. Python UDFs are supported in single user access mode.
On all supported Databricks Runtime versions:
Unity Catalog UDFs do not support accessing volume file paths.
You cannot access volumes from RDDs.
You cannot use spark-submit with JARs stored in a volume.
You cannot define dependencies to other libraries accessed via volume paths inside a wheel or JAR file.
You cannot list Unity Catalog objects using the /Volumes/<catalog-name> or /Volumes/<catalog-name>/<schema-name> patterns. You must use a fully-qualified path that includes a volume name.
The DBFS endpoint for the REST API does not support volumes paths.
Volumes are excluded from global search results in the Databricks workspace.
You cannot specify volumes as the destination for cluster log delivery.
%sh mv is not supported for moving files between volumes. Use dbutils.fs.mv or %sh cp instead.
You cannot create a custom Hadoop file system with volumes, meaning the following is not supported:
I have already run anaconda as an administrator, but it still shows “PermissionError: [Errno 13] Permission denied”. I thought it was because the folder attribute is read-only, so i tried several ways to change this such as CMD checks and powershell checks but the folder still shows read-only. The windows support said that this was not the issue and the display of read-only is something can’t be changed. So what am i suppose to do next. Thanks.
What code are you executing to get this error?
I’m new here and don’t know much about the format. If there is anything inappropriate, please let me know. Thank you.
What is the full traceback? What are the relevant variables at that point in time?
Traceback (most recent call last): File “D:\Project\guben\yunxing2.py”, line 129, in main() File “D:\Project\guben\yunxing2.py”, line 118, in main recorded_text = recognize_speech(file_path) ^^^^^^^^^^^^^^^^^^^^^^^^^^^ File “D:\Project\guben\yunxing2.py”, line 75, in recognize_speech wf = wave.open(file_path, “rb”) ^^^^^^^^^^^^^^^^^^^^^^^^^^ File “D:\Anaconda\envs\myenv\Lib\wave.py”, line 649, in open return Wave_read(f) ^^^^^^^^^^^^ File “D:\Anaconda\envs\myenv\Lib\wave.py”, line 282, in init f = builtins.open(f, ‘rb’) ^^^^^^^^^^^^^^^^^^^^^^ PermissionError: [Errno 13] Permission denied: ‘D:\Project\guben\record_save’
So the problem or that you are trying to open a folder as it is were a file, which didn’t work. On windows this produces a Permission Error instead of something more helpful.
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Using zip file, I indicate files locate within an other folder for example: './data/2003-2007/metropolis/Matrix_0_1_0.csv'
My problem is that, when I extract it, the files are found in ./data/2003-2007/metropolis/Matrix_0_1_0.csv , while I would like it to be extract in ./
Here is my code:
Here is the print of src and dst:
As shown in: Python: Getting files into an archive without the directory?
The solution is:
Maybe better solution in this case to use tarfile :
As written in the documentation there is a parameter of ZipFile.write called arcname .
So, you can use is to name your file(s) as you want. Note: to be able to make it dynamical, you should consider to import pathlib library. In your case:
If you want to get every files under a directory, and then make a zip from those files, you can do something like this:
I know it was years ago, but maybe it will be useful for someone.
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Here we pass the directory to be zipped to the get_all_file_paths() function and obtain a list containing all file paths. with ZipFile('my_python_files.zip','w') as zip: Here, we create a ZipFile object in WRITE mode this time. for file in file_paths: zip.write(file) Here, we write all the files to the zip file one by one using write method.
ZipFile Objects¶ class zipfile. ZipFile (file, mode = 'r', compression = ZIP_STORED, allowZip64 = True, compresslevel = None, *, strict_timestamps = True, metadata_encoding = None) ¶. Open a ZIP file, where file can be a path to a file (a string), a file-like object or a path-like object.. The mode parameter should be 'r' to read an existing file, 'w' to truncate and write a new file, 'a' to ...
Using Python from the shell. You can do this with Python from the shell also using the zipfile module: $ python -m zipfile -c zipname sourcedir. Where zipname is the name of the destination file you want (add .zip if you want it, it won't do it automatically) and sourcedir is the path to the directory.
Knowing how to create, read, write, populate, extract, and list ZIP files using the zipfile module is a useful skill to have as a Python developer or a DevOps engineer. In this tutorial, you'll learn how to: Read, write, and extract files from ZIP files with Python's zipfile; Read metadata about the content of ZIP files using zipfile
myzip.write( 'document.txt' ) In this code, we're creating a new zip archive named compressed_file.zip and just adding document.txt to it. The 'w' parameter means that we're opening the zip file in write mode. Now, if you check your directory, you should see a new zip file named compressed_file.zip.
In Python, the zipfile module allows you to zip and unzip files, i.e., compress files into a ZIP file and extract a ZIP file. zipfile — Work with ZIP archives — Python 3.11.4 documentation. You can also easily zip a directory (folder) and unzip a ZIP file using the make_archive() and unpack_archive() functions from the shutil module.
You can also create a zip file containing multiple files. Here is an example: 'file_to_compressed2.txt', 'file_to_compressed3.txt'. zip_object.write(file_name, compress_type=zipfile.ZIP_DEFLATED) In the above example, we defined the names of multiple source files in a list.
Python Interview Questions on Python Zip Files. Q1. Write a program to print all the contents of the zip file 'EmployeeReport.zip'. Ans 1. Complete code is as follows: from zipfile import ZipFile with ZipFile('EmployeeReport.zip', 'r') as file: file.printdir() Output.
zip .extract( 'file1.txt', '/Users/datagy/') Note that we're opening the zip file using the 'r' method, indicating we want to read the file. We then instruct Python to extract file1.txt and place it into the /Users/datagy/ directory. In many cases, you'll want to extract more than a single file.
zipfile Module. The first thing you need to work with zip files in python is zipfile module. This module provides tools to create, read, write, append, and list a ZIP file. This module does not currently handle multi-disk ZIP files. It can handle ZIP files that use the ZIP64 extensions (ZIP files that are more than 4 GByte in size).
Python's print statement takes a keyword argument called file that decides which stream to write the given message/objects. Its value is a " file-like object." See the definition of print,
Creating uncompressed ZIP file in Python. Uncompressed ZIP files do not reduce the size of the original directory. As no compression is sharing uncompressed ZIP files over a network has no advantage as compared to sharing the original file. Using shutil.make_archive to create Zip file. Python has a standard library shutil which can be used to ...
Files can be compressed without losing any data. Python has built-in support for ZIP files. #more. In this article, we will learn how ZIP files can be read, written, extracted, and listed in Python. List ZIP file contents¶ The zipfile module in Python, a part of the built-in libraries, can be used to manipulate ZIP files. It is advised to work ...
Create a zip archive from multiple files in Python. Steps are, Create a ZipFile object by passing the new file name and mode as 'w' (write mode). It will create a new zip file and open it within ZipFile object. Call write () function on ZipFile object to add the files in it. call close () on ZipFile object to Close the zip file.
It supports methods for reading data about existing archives as well as modifying the archives by adding additional files. To read the names of the files in an existing archive, use namelist (): import zipfile zf = zipfile.ZipFile('example.zip', 'r') print zf.namelist() The return value is a list of strings with the names of the archive ...
In this article, we will see a Python program that will crack the zip file's password using the brute force method. The ZIP file format is a common archive and compression standard. It is used to compress files. Sometimes, compressed files are confidential and the owner doesn't want to give its access to every individual. Hence, the zip file is pro
10. More Python modules¶. gzip - compresses/decompresses binary data, reads/writes data into *.gzip file.. zipfile - creates, adds, reads, writes to zip archives.. getpass - reads password from keyboard.. glob - finds files with matched regexp patterns.. json - encodes/decodes python object into json, reads/writes jason files.. argparse - passes parameters to a python script.
Now that the application works, you will write automated tests for it in the next section. Step 2 — Writing your first test. In this section and the following ones, you'll use unittest to write automated tests that ensure the format_file_size() function works correctly. This includes verifying the proper formatting of various file sizes.
How to set up an existing Snowpark project on your local system using a Python IDE. Add a Python UDF to the existing codebase and deploy the function directly in Snowflake. Validate the function deployment locally and test from Snowflake as well. Dive deep into the inner workings of the Snowpark Python UDF deployment.
A Python lehetővé teszi a zip/tar létrehozását archives gyorsan. Following parancs a teljes könyvtárat tömöríti, shutil.make_archive(kimeneti_fájlnév, 'zip', könyvtár_neve)
with ZipFile(read_file, 'r') as zipread: with ZipFile(file_write_buffer, 'w', ZIP_DEFLATED) as zipwrite: for item in zipread.infolist(): # Copy all ZipInfo attributes for each file since defaults are not preseved dest.CRC = item.CRC dest.date_time = item.date_time dest.create_system = item.create_system dest.compress_type = item.compress_type dest.external_attr = item.external_attr dest ...
总结. 本文详细介绍了如何使用Python自动化处理压缩文件,包括读取、创建、添加和解压ZIP和TAR文件。通过使用Python内置的zipfile、tarfile和shutil模块,开发者可以高效地管理压缩文件,实现自动化文件处理。文中提供了丰富的示例代码,展示了如何在实际应用中使用这些模块进行文件备份和解压操作。
Tutorial¶. In this tutorial, you will create a database of Monty Python movies using basic sqlite3 functionality. It assumes a fundamental understanding of database concepts, including cursors and transactions.. First, we need to create a new database and open a database connection to allow sqlite3 to work with it. Call sqlite3.connect() to create a connection to the database tutorial.db in ...
mouse_dpi int: Mouse DPI.; mouse_sensitivity float: Aim sensitivity.; mouse_fov_width int: The current horizontal value of the viewing angle in the game.; mouse_fov_height int: The current vertical value of the viewing angle in the game.; mouse_lock_target bool: True: Press once to permanently aim at the target, press again to turn off the aiming.False: Hold down the button to constantly aim ...
Because a private webserver can't access the PyPI repository through the internet, pip will install the dependencies from the .zip file. If you're using a public webserver configuration, you also benefit from a static .zip file, which makes sure the package information remains unchanged until it is explicitly rebuilt.
The path to access volumes is the same whether you use Apache Spark, SQL, Python, or other languages and libraries. This differs from legacy access patterns for files in object storage bound to a Databricks workspace. The path to access files in volumes uses the following format: /
11. ZipFile.write(filename, [arcname[, compress_type]]) takes the name of a local file to be added to the zip file. To write data from a bytearray or bytes object you need to use the ZipFile.writestr(zinfo_or_arcname, bytes[, compress_type]) method instead shown below: zipFile.writestr('name_of_file_in_archive', zipContents) Note: if request ...
I have already run anaconda as an administrator, but it still shows "PermissionError: [Errno 13] Permission denied". I thought it was because the folder attribute is read-only, so i tried several ways to change this such as CMD checks and powershell checks but the folder still shows read-only. The windows support said that this was not the issue and the display of read-only is something ...
In app_config.py add metioned below lines in the beginning of file; import dotenv; dotenv.load_dotenv() We are all set lets run . python app.py . Conclusion: As we conclude this guide on mastering Microsoft Entra, you now possess the knowledge to enhance your application's security and streamline user management.
As shown in: Python: Getting files into an archive without the directory? The solution is: ''' zip_file: @src: Iterable object containing one or more element @dst: filename (path/filename if needed) @arcname: Iterable object containing the names we want to give to the elements in the archive (has to correspond to src) ''' def zip_files(src, dst, arcname=None): zip_ = zipfile.ZipFile(dst, 'w ...