python操作崖山数据库进行增删改查

在Python中操作MySQL（也称为MariaDB，因为它们兼容）这样的关系型数据库，最常用的是使用像`pymysql`或者`mysql-connector-python`这样的库。对于崖山数据库（实际上可能是MySQL误拼，这里假设你是指MySQL），下面是一个基本的例子，展示了如何使用Python进行增删改查操作：

import pymysql

# 连接到数据库
def connect_db(host, user, password, db):
    connection = pymysql.connect(
        host=host,
        user=user,
        password=password,
        database=db,
        charset='utf8mb4',
        cursorclass=pymysql.cursors.DictCursor  # 使用字典形式的游标
    )
    return connection

# 关闭连接
def close_conn(connection):
    connection.close()

# 插入数据
def insert_data(conn, table_name, columns, values):
    with conn.cursor() as cursor:
        sql = f"INSERT INTO {table_name} ({', '.join(columns)}) VALUES ({', '.join(['%s'] * len(values))})"
        cursor.execute(sql, values)
    conn.commit()

# 查询数据
def select_data(conn, table_name, conditions=None, fields=None):
    with conn.cursor() as cursor:
        if conditions:
            sql = f"SELECT {(', '.join(fields))} FROM {table_name} WHERE {conditions}"
        else:
            sql = f"SELECT {(', '.join(fields))} FROM {table_name}"
        cursor.execute(sql)
        return cursor.fetchall()

# 更新数据
def update_data(conn, table_name, set_values, where_conditions):
    with conn.cursor() as cursor:
        sql = f"UPDATE {table_name} SET {set_values} WHERE {where_conditions}"
        cursor.execute(sql)
    conn.commit()

# 删除数据
def delete_data(conn, table_name, where_conditions):
    with conn.cursor() as cursor:
        sql = f"DELETE FROM {table_name} WHERE {where_conditions}"
        cursor.execute(sql)
    conn.commit()

# 示例用法
connection = connect_db('localhost', 'username', 'password', 'database_name')
try:
    # 插入一条记录
    insert_data(connection, 'users', ['name', 'email'], ('John Doe', 'john.doe@example.com'))

    # 查询所有用户
    users = select_data(connection, 'users')

    # 更新某个用户的邮箱
    update_data(connection, 'users', "email='%s'", "name='John Doe'")

    # 删除邮件地址为'john.doe@example.com'的用户
    delete_data(connection, 'users', "email='john.doe@example.com'")
finally:
    close_conn(connection)