使用Python实现批量删除MYSQL数据库的全部外键

装不满的克莱因瓶2024-04-25 11:34

我先说下场景，昨天因为我们使用了Java工作流框架flowable，它自动生成了许多工作流相关的表，但是这些表都有外键关联，如果单纯的使用sql语句去一个一个的删除外键，那会非常麻烦，所以我写了一个Python脚本来进行批量删除。

前提是你要有个Python环境...

先安装mysql驱动依赖：

bash 复制代码

pip install mysql-connector-python

因为代码非常简单，所以直接把代码粘出来，改下你mysql的连接信息，直接右键运行即可。

python 复制代码

import mysql.connector

def delete_foreign_keys(host, port, user, password, database):
    try:
        # 连接到数据库
        conn = mysql.connector.connect(
            host=host,
            port=port,
            user=user,
            password=password,
            database=database
        )

        cursor = conn.cursor()

        # 查询外键约束
        cursor.execute("""
            SELECT 
                CONSTRAINT_NAME,
                TABLE_NAME
            FROM
                INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS
            WHERE
                UNIQUE_CONSTRAINT_SCHEMA = %s;
        """, (database,))

        foreign_keys = cursor.fetchall()

        # 生成删除外键约束的 SQL 语句并执行
        for fk in foreign_keys:
            constraint_name, table_name = fk
            cursor.execute(f"ALTER TABLE {table_name} DROP FOREIGN KEY {constraint_name};")
            print(f"Deleted foreign key constraint {constraint_name} from table {table_name}")

        conn.commit()
        print("All foreign key constraints deleted successfully!")

    except mysql.connector.Error as error:
        print("Error while connecting to MySQL", error)

    finally:
        if conn.is_connected():
            cursor.close()
            conn.close()
            print("MySQL connection is closed")

# 设置数据库连接参数
host = '127.0.0.1'
port = 3306  # MySQL 默认端口号
user = 'root'
password = 'root'
database = 'mydatabase'

# 调用函数删除外键约束
delete_foreign_keys(host, port, user, password, database)