python 封装单例mysql

import mysql.connector

def singleton(cls):
    instances = {}
    def getinstance():
        if cls not in instances:
            instances[cls] = cls()
        return instances[cls]
    return getinstance

@singleton
class MySQLConnection:
    def __init__(self):
        self.connection = mysql.connector.connect(
            host="localhost",
            user="user",
            password="password",
            database="database"
        )

    def execute_query(self, query):
        cursor = self.connection.cursor()
        cursor.execute(query)
        result = cursor.fetchall()
        cursor.close()
        return result

# 使用示例
db_connection = MySQLConnection()
result = db_connection.execute_query("SELECT * FROM table")
print(result)