implementing Multithreading and SQLite Database Locking in Python 3.11
I'm trying to figure out I'm a bit lost with I'm running into a question while trying to use multithreading to handle multiple database queries in my Python 3.11 application that uses SQLite... I have a simple function that executes a read query on a SQLite database, and I spawn multiple threads to perform this function concurrently. However, I'm working with a `sqlite3.OperationalError: database is locked` behavior intermittently. My code looks something like this: ```python import sqlite3 import threading def read_data(query): conn = sqlite3.connect('my_database.db') cursor = conn.cursor() cursor.execute(query) results = cursor.fetchall() cursor.close() conn.close() return results queries = ["SELECT * FROM my_table WHERE id = ?" % i for i in range(10)] threads = [] for query in queries: thread = threading.Thread(target=read_data, args=(query,)) threads.append(thread) thread.start() for thread in threads: thread.join() ``` I tried using `conn = sqlite3.connect('my_database.db', timeout=5)` to set a timeout, but this only reduces the frequency of the errors without completely resolving them. I've also considered switching to `sqlite3.Connection`'s `PRAGMA journal_mode=WAL;` setting to enable Write-Ahead Logging, which might help with concurrency, but I haven't implemented that yet. Should I be looking into connection pooling, or is there a better way to manage SQLite connections in a multithreaded environment? I'm concerned about both performance and data integrity, so any advice on best practices for using SQLite with threads would be greatly appreciated. My development environment is macOS. This issue appeared after updating to Python 3.10. Has anyone else encountered this? I'm working on a CLI tool that needs to handle this.