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Database scaling & optimization

Indexing, connection pooling, read replicas, query tuning, and throughput-aware SQL.

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Database scaling & optimization easy

How to Avoid SELECT * and Mock SQL Column Queries in Python

Mock a SQLite cursor to verify that queries specify explicit columns instead of using SELECT *.

sqlite mock testing
Python 
import sqlite3
from unittest.mock import Mock, patch


def get_user_emails(connection):
    """Fetch only the required columns instead of SELECT *."""
    cursor = connection.cursor()
    cursor.execute("SELECT email FROM users")
    return [row[0] for row in cursor.fetchall()]


def test_get_user_emails_specific_colu…
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