# 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. The explicit management of transactions might be a bit tricky at first, but it can certainly help you make the most of sqlite3.If you decide you do want to store the database from memory to a file, you can use the backup() function. I hope you now have a good understanding of what SQLite is, how you can use it for your Python projects, and how some of its advanced features work. execute ( "SELECT * FROM student" ) for row in findRecords : print (row ) Insert_command (conn, 4, 'Joseph', 'Random' )įindRecords = cursor. Insert_command (conn, 3, 'Stephan', 'Taylor' ) Insert_command (conn, 2, 'Lucy', 'Jacobs' ) Insert_command (conn, 1, 'John', 'Smith' ) execute (create_query ) print ( "Table created!" ) # Insert and Read operation cursor ( ) print ( "Database created!" ) # Create operationĬreate_query = '''CREATE TABLE IF NOT EXISTS student(Ĭursor. connect (dbName, isolation_level = None )Ĭursor = conn. Error as e : print ( "Got an error: ", e ) print ( "Aborting." )Ĭonn = sqlite3. execute (command, (student_id, name, surname, ) )Ĭur. The following code is a rewriting of the previous code, but with the explicit usage of transactions: import sqlite3ĭbName = 'database.db' def insert_command (conn, student_id, name, surname ) :Ĭommand = 'INSERT INTO student VALUES (?, ?, ?)'Ĭur. By setting isolation_level to None, we force sqlite3 to never open transactions implicitly. How? By using the function call nnect(dbName, isolation_level=None) instead of nnect(dbName).
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