Python 链接数据库,快速操作数据库类。让你操作数据库so so 的

import pymysql


class DatabaseHandler:

    def __init__(self):
        self.db = pymysql.connect(host='127.0.0.1', user='root', db='test')
        # 创建游标对象
        self.cursor = self.db.cursor()

    # def __del__(self):
    #     self.close()

    def close(self):
        self.cursor.close()
        self.db.close()

    def delete_data(self, table_name: str, condition: dict) -> int:
        where_clause = " AND ".join(f"`{key}`='{value}'" for key, value in condition.items())
        sql = f"DELETE FROM `{table_name}` WHERE {where_clause};"
        affected_rows = self.cursor.execute(sql)
        self.db.commit()
        return affected_rows

    def select_data(self, table_name: str, columns: list = None, condition: dict = None, limit: int = None) -> list:
        if not columns:
            select_clause = "*"
        else:
            select_clause = ", ".join(f"`{column}`" for column in columns)

        where_clause = ""
        if condition:
            where_clause = " AND ".join(f"`{key}`='{value}'" for key, value in condition.items())
            where_clause = f"WHERE {where_clause}"

        limit_clause = ""
        if limit:
            limit_clause = f"LIMIT {limit}"

        sql = f"SELECT {select_clause} FROM `{table_name}` {where_clause} {limit_clause};"
        self.cursor.execute(sql)
        rows = self.cursor.fetchall()
        return rows

    def insert_data_by_array(self, info: dict, table_name: str) -> int:
        keys = ", ".join(f"`{key}`" for key in info.keys())
        values = ", ".join(f"'{value}'" for value in info.values())
        sql = f"INSERT INTO `{table_name}`({keys}) VALUES ({values});"
        self.cursor.execute(sql)
        self.db.commit()

        last_inserted_id = self.cursor.lastrowid
        return last_inserted_id

    def update_data(self, info: dict, table_name: str, condition: dict) -> int:
        set_clause = ", ".join(f"`{key}`='{value}'" for key, value in info.items())
        where_clause = " AND ".join(f"`{key}`='{value}'" for key, value in condition.items())

        sql = f"UPDATE `{table_name}` SET {set_clause} WHERE {where_clause};"
        affected_rows = self.cursor.execute(sql)
        self.db.commit()
        return affected_rows