![]() ![]() If your operating system does not provide a Python interpreter, you can go to to download an installer. Then you will learn how to retrieve the blobs and convert them back into regular files for use by your application. In this tutorial, you will learn about blob (binary large object) data and why you need to convert your multimedia files to binary objects in order to store them properly in a database. You could store the files directly in the server’s file system, integrate with APIs from cloud storage platforms, or you can learn how to store the information in your database! Rows = cursor.If you're a developer who is building out a website that allows users to upload image files for reasons such as updating a profile picture, sharing images with other users, or utilizing other multimedia files, you will find yourself wondering, "what's the safest way to save their data?". from sqlite3 import connect, Rowĭb = connect('test.db') # Using the database created in previous example This method is more convenient to use as the programmer, but is less efficient than using the default tuple format from the previous example. This example shows you how to use a different row factory which will provide you a dictionary-like object that lets you access fields using a case-insensitive keys as well as providing a keys() function to get the list of columns in order. # Or fetch a single row with `fetchone()` # Or fetch a specific amount of rows with `fetchmany()` Rows = cursor.execute('SELECT * FROM users ORDER BY username ASC')Īll_rows = rows.fetchall() # Get a list of rows as tuples ![]() # Query for rows and then use `fetchall()` to get as a list Rows = cursor.execute('SELECT * FROM users LIMIT 100') ![]() from sqlite3 import connectĬursor.execute('INSERT INTO users (username, email) VALUES ("nanodano", Query for rows and then iterate through results The next example will show how to use sqlite3.Row as the row factory to give you dictionary-like result objects. The first example demonstrates the tuples which is very efficient. This example shows both methods.īy default, the database cursor will return tuples with the row data. You can iterate through the data with a for loop or you can use fetchone(), fetchmany() or fetchall() to extract the results. Once you fetch the results you have a couple options for consuming the data. This example shows how to fetch results from a database. ('admin', INTO users (username, email) VALUES (?, ?)", row_data) To insert multiple rows at once you can use executemany(). # Until you commit, the changes will not be saved, only in memory! from sqlite3 import connectĬursor.execute('CREATE TABLE IF NOT EXISTS users (username TEXT, email TEXT)')Ĭursor.execute('INSERT INTO users (username, email) VALUES ("admin", INTO users (username, email) VALUES ("nanodano", # Id of inserted row This example shows how to insert rows to a database and how to get the row ID of the last row inserted. To insert rows, you call execute() like you do with any other SQL statement. Note that if you are not using the database actively, you can safely just copy the database file and you don't have to use this backup() method. # Now use `memory_db` without modifying disk db ![]() # transient copy in memory without modifying the file # Load the contents of a database file on disk to a This creates a unique copy of the database in to memory that is separate from the file on disk. This is different from loading the file directly where SQL statements would alter the file. This example shows how to take the contents of a database on disk and load it in to memory. This first example shows how to backup a memory database to a file. You can use it to take a memory database and store it in a file, but you can also do the reverse, that is, "backup" a database from a file in to a :memory: database, creating a copy in memory without directly loading/modifying the copy on disk. The backup() function essentially copies one database to another. If you decide you do want to store the database from memory to a file, you can use the backup() function. ![]()
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