Python DBUtils数据连接池与mysql配合用法_MySQL
python
# -*- coding: UTF-8 -*-"""desc:数据库操作类@note:1、执行带参数的SQL时,请先用sql语句指定需要输入的条件列表,然后再用tuple/list进行条件批配2、在格式SQL中不需要使用引号指定数据类型,系统会根据输入参数自动识别3、在输入的值中不需要使用转意函数,系统会自动处理"""import MySQLdbfrom MySQLdb.cursors import DictCursorfrom DBUtils.PooledDB import PooledDBimport Config"""Config是一些数据库的配置文件"""class Mysql(object): """ MYSQL数据库对象,负责产生数据库连接 , 此类中的连接采用连接池实现 获取连接对象:conn = Mysql.getConn() 释放连接对象;conn.close()或del conn """ #连接池对象 __pool = None def __init__(self): """ 数据库构造函数,从连接池中取出连接,并生成操作游标 """# self._conn = MySQLdb.connect(host=Config.DBHOST , port=Config.DBPORT , user=Config.DBUSER , passwd=Config.DBPWD ,# db=Config.DBNAME,use_unicode=False,charset=Config.DBCHAR,cursorclass=DictCursor) self._conn = Mysql.__getConn() self._cursor = self._conn.cursor() @staticmethod def __getConn(): """ @summary: 静态方法,从连接池中取出连接 @return MySQLdb.connection """ if Mysql.__pool is None: __pool = PooledDB(creator=MySQLdb, mincached=1 , maxcached=20 , host=Config.DBHOST , port=Config.DBPORT , user=Config.DBUSER , passwd=Config.DBPWD , db=Config.DBNAME,use_unicode=False,charset=Config.DBCHAR,cursorclass=DictCursor) return __pool.connection() def getAll(self,sql,param=None): """ @summary: 执行查询,并取出所有结果集 @param sql:查询SQL,如果有查询条件,请只指定条件列表,并将条件值使用参数[param]传递进来 @param param: 可选参数,条件列表值(元组/列表) @return: result list/boolean 查询到的结果集 """ if param is None: count = self._cursor.execute(sql) else: count = self._cursor.execute(sql,param) if count>0: result = self._cursor.fetchall() else: result = False return result def getOne(self,sql,param=None): """ @summary: 执行查询,并取出第一条 @param sql:查询SQL,如果有查询条件,请只指定条件列表,并将条件值使用参数[param]传递进来 @param param: 可选参数,条件列表值(元组/列表) @return: result list/boolean 查询到的结果集 """ if param is None: count = self._cursor.execute(sql) else: count = self._cursor.execute(sql,param) if count>0: result = self._cursor.fetchone() else: result = False return result def getMany(self,sql,num,param=None): """ @summary: 执行查询,并取出num条结果 @param sql:查询SQL,如果有查询条件,请只指定条件列表,并将条件值使用参数[param]传递进来 @param num:取得的结果条数 @param param: 可选参数,条件列表值(元组/列表) @return: result list/boolean 查询到的结果集 """ if param is None: count = self._cursor.execute(sql) else: count = self._cursor.execute(sql,param) if count>0: result = self._cursor.fetchmany(num) else: result = False return result def insertOne(self,sql,value): """ @summary: 向数据表插入一条记录 @param sql:要插入的SQL格式 @param value:要插入的记录数据tuple/list @return: insertId 受影响的行数 """ self._cursor.execute(sql,value) return self.__getInsertId() def insertMany(self,sql,values): """ @summary: 向数据表插入多条记录 @param sql:要插入的SQL格式 @param values:要插入的记录数据tuple(tuple)/list[list] @return: count 受影响的行数 """ count = self._cursor.executemany(sql,values) return count def __getInsertId(self): """ 获取当前连接最后一次插入操作生成的id,如果没有则为0 """ self._cursor.execute("SELECT @@IDENTITY AS id") result = self._cursor.fetchall() return result[0]['id'] def __query(self,sql,param=None): if param is None: count = self._cursor.execute(sql) else: count = self._cursor.execute(sql,param) return count def update(self,sql,param=None): """ @summary: 更新数据表记录 @param sql: SQL格式及条件,使用(%s,%s) @param param: 要更新的 值 tuple/list @return: count 受影响的行数 """ return self.__query(sql,param) def delete(self,sql,param=None): """ @summary: 删除数据表记录 @param sql: SQL格式及条件,使用(%s,%s) @param param: 要删除的条件 值 tuple/list @return: count 受影响的行数 """ return self.__query(sql,param) def begin(self): """ @summary: 开启事务 """ self._conn.autocommit(0) def end(self,option='commit'): """ @summary: 结束事务 """ if option=='commit': self._conn.commit() else: self._conn.rollback() def dispose(self,isEnd=1): """ @summary: 释放连接池资源 """ if isEnd==1: self.end('commit') else: self.end('rollback'); self._cursor.close() self._conn.close()

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