当列不存在于其他表中时更新列[大数据集]

import sqlite3

def update_column_if_exists(source_conn, target_conn, table_name, column_name, new_value):
    # 检查源表中是否存在该列
    source_cursor = source_conn.cursor()
    source_cursor.execute(f"PRAGMA table_info({table_name});")
    columns = [column[1] for column in source_cursor.fetchall()]
    
    if column_name in columns:
        # 列存在，执行更新操作
        target_cursor = target_conn.cursor()
        try:
            with target_conn:
                target_cursor.execute(f"UPDATE {table_name} SET {column_name} = ? WHERE some_condition;", (new_value,))
        except sqlite3.Error as e:
            print(f"An error occurred: {e}")
    else:
        print(f"Column {column_name} does not exist in the source table.")

# 示例使用
source_db = sqlite3.connect('source.db')
target_db = sqlite3.connect('target.db')

update_column_if_exists(source_db, target_db, 'users', 'email', 'new_email@example.com')