python操作MySQL类

#!/usr/bin/python3
# -*- coding: utf-8 -*-
import pymysql
import re

class MysqldbHelper(object): # 继承object类所有方法
    '''
    构造方法：
    config = {
        'host': '127.0.0.1',
        'port': 3306,
        'user': 'root',
        'passwd': 'root',
        'charset':'utf8',
        'cursorclass':pymysql.cursors.DictCursor
        }
    conn = pymysql.connect(**config)
    conn.autocommit(1)
    cursor = conn.cursor()
    '''
    def __init__(self , config):
        self.host = config['host']
        self.username = config['user']
        self.password = config['passwd']
        self.port = config['port']
        self.con = None
        self.cur = None

        try:
            self.con = pymysql.connect(**config)
            self.con.autocommit(1)
            # 所有的查询，都在连接 con 的一个模块 cursor 上面运行的
            self.cur = self.con.cursor()
        except:
            print("DataBase connect error,please check the db config.")

    # 关闭数据库连接
    def close(self):
        if not  self.con:
            self.con.close()
        else:
            print("DataBase doesn't connect,close connectiong error;please check the db config.")

    # 创建数据库
    def createDataBase(self,DB_NAME):
        # 创建数据库
        self.cur.execute('CREATE DATABASE IF NOT EXISTS %s DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci' % DB_NAME)
        self.con.select_db(DB_NAME)
        print('creatDatabase:' + DB_NAME)

    # 选择数据库
    def selectDataBase(self,DB_NAME):
        self.con.select_db(DB_NAME)

    # 获取数据库版本号
    def getVersion(self):
        self.cur.execute("SELECT VERSION()")
        return self.getOneData()

    # 获取上个查询的结果
    def getOneData(self):
        # 取得上个查询的结果，是单个结果
        data = self.cur.fetchone()
        return data

    # 查看所有表
    def showTables(self):
        tables = self.executeSql("show tables;")
        print(tables)

    # 创建数据库表
    def creatTable(self, tablename, attrdict, constraint = "PRIMARY KEY(`id`)"):
        """创建数据库表
            args：
                tablename  ：表名字
                attrdict   ：属性键值对,{'book_name':'varchar(200) NOT NULL'...}
                constraint ：主外键约束,PRIMARY KEY(`id`)
        """
        #　判断表是否存在
        if self.isExistTable(tablename):
            print("%s is exit" % tablename)
            return
        sql = ''
        sql_mid = '`id` bigint(11) NOT NULL AUTO_INCREMENT,'
        for attr,value in attrdict.items():
            sql_mid = sql_mid + '`'+attr + '`'+' '+ value+','
        sql = sql + 'CREATE TABLE IF NOT EXISTS %s ('%tablename
        sql = sql + sql_mid
        sql = sql + constraint
        sql = sql + ') ENGINE=InnoDB DEFAULT CHARSET=utf8'
        print('creatTable:'+sql)
        self.executeCommit(sql)

    def executeSql(self,sql=''):
        """
            执行sql语句，针对读操作返回结果集
            args：
                sql  ：sql语句
        """
        try:
            self.cur.execute(sql)
            records = self.cur.fetchall()
            return records
        except pymysql.Error as e:
            error = '执行sql语句失败(%s): %s' %(e.args[0],e.args[1])
            print(error)

    def executeCommit(self,sql=''):
        """
        执行数据库sql语句，针对更新,删除,事务等操作失败时回滚
        """
        try:
            self.cur.execute(sql)
            self.con.commit()
        except pymysql.Error as e:
            self.con.rollback()
            error = '执行数据库sql语句失败(%s): %s' %(e.args[0],e.args[1])
            print("error:", error)
            return error

    def insert(self, tablename, params):
        """
            往表里插入数据，单条数据
            args：
                tablename  ：表名字
                key        ：属性键
                value      ：属性值
        """
        key = []
        value = []
        # for tmpkey, tmpvalue in params.items():
        #     key.append(tmpkey)
        #     if isinstance(tmpvalue, str):
        #         value.append("\'" + tmpvalue + "\'")
        #     else:
        #         value.append(tmpvalue)
        # attrs_sql = '('+','.join(key)+')'
        # values_sql = ' values('+','.join(value)+')'
        for k,v in params.items():
            key.append('`'+ k + '`')
            value.append(v)
        sql = 'insert into %s'%tablename
        # sql = sql + attrs_sql + values_sql
        sql = sql + '('+','.join(key)+')' + ' values ' + str(tuple(value))
        print('_insert:'+sql)
        self.executeCommit(sql)

    def select(self, tablename, cond_dict='', order='', fields='*'):
        """查询数据
            args：
                tablename  ：表名字
                cond_dict  ：查询条件
                order      ：排序条件
            example：
                print mydb.select(table)
                print mydb.select(table, fields=["name"])
                print mydb.select(table, fields=["name", "age"])
                print mydb.select(table, fields=["age", "name"])
        """
        consql = ' '
        if cond_dict!='':
            for k, v in cond_dict.items():
                consql = consql+'`'+k +'`'+ '=' + '"'+v + '"' + ' and'
        consql = consql + ' 1=1 '
        if fields == "*":
            sql = 'select * from %s where ' % tablename
        else:
            if isinstance(fields, list):
                fields = ",".join(fields)
                sql = 'select %s from %s where ' % (fields, tablename)
            else:
                print("fields input error, please input list fields.")
        sql = sql + consql + order
        print('select:' + sql)
        return self.executeSql(sql)

    def insertMany(self,table, attrs, values):
        """插入多条数据
            args：
                tablename  ：表名字
                attrs      ：属性键
                values     ：属性值
            example：
                table='test_mysqldb'
                key = ["id" ,"name", "age"]
                value = [[101, "liuqiao", "25"], [102,"liuqiao1", "26"], [103 ,"liuqiao2", "27"], [104 ,"liuqiao3", "28"]]
                mydb.insertMany(table, key, value)
        """
        values_sql = ['%s' for v in attrs]
        attrs_sql = '('+','.join(attrs)+')'
        values_sql = ' values('+','.join(values_sql)+')'
        sql = 'insert into %s'% table
        sql = sql + attrs_sql + values_sql
        print('insertMany:'+sql)
        try:
            print(sql)
            for i in range(0,len(values),20000):
                    self.cur.executemany(sql,values[i:i+20000])
                    self.con.commit()
        except pymysql.Error as e:
            self.con.rollback()
            error = 'insertMany executemany failed! ERROR (%s): %s' %(e.args[0],e.args[1])
            print(error)

    def delete(self, tablename, cond_dict):
        """删除数据
            args：
                tablename  ：表名字
                cond_dict  ：删除条件字典
            example：
                params = {"name" : "caixinglong", "age" : "38"}
                mydb.delete(table, params)
        """
        consql = ' '
        if cond_dict!='':
            for k, v in cond_dict.items():
                if isinstance(v, str):
                    v = "\'" + v + "\'"
                consql = consql + tablename + "." + k + '=' + v + ' and '
        consql = consql + ' 1=1 '
        sql = "DELETE FROM %s where%s" % (tablename, consql)
        print(sql)
        return self.executeCommit(sql)

    def update(self, tablename, attrs_dict, cond_dict):
        """更新数据
            args：
                tablename  ：表名字
                attrs_dict  ：更新属性键值对字典
                cond_dict  ：更新条件字典
            example：
                params = {"name" : "caixinglong", "age" : "38"}
                cond_dict = {"name" : "liuqiao", "age" : "18"}
                mydb.update(table, params, cond_dict)
        """
        attrs_list = []
        consql = ' '
        for tmpkey, tmpvalue in attrs_dict.items():
            attrs_list.append("`" + tmpkey + "`" + "=" +"\'" + tmpvalue + "\'")
        attrs_sql = ",".join(attrs_list)
        print("attrs_sql:", attrs_sql)
        if cond_dict!='':
            for k, v in cond_dict.items():
                if isinstance(v, str):
                    v = "\'" + v + "\'"
                consql = consql + "`" + tablename +"`." + "`" + k + "`" + '=' + v + ' and '
        consql = consql + ' 1=1 '
        sql = "UPDATE %s SET %s where%s" % (tablename, attrs_sql, consql)
        print(sql)
        return self.executeCommit(sql)

    def dropTable(self, tablename):
        """删除数据库表
            args：
                tablename  ：表名字
        """
        sql = "DROP TABLE  %s" % tablename
        self.executeCommit(sql)

    def deleteTable(self, tablename):
        """清空数据库表
            args：
                tablename  ：表名字
        """
        sql = "DELETE FROM %s" % tablename
        print("sql=",sql)
        self.executeCommit(sql)

    def isExistTable(self, tablename):
        """判断数据表是否存在
            args：
                tablename  ：表名字
            Return:
                存在返回True，不存在返回False
        """
        sql = "select * from %s" % tablename
        result = self.executeCommit(sql)
        if result is None:
            return True
        else:
            if re.search("doesn't exist", result):
                return False
            else:
                return True


if __name__ == "__main__":

    # 定义数据库访问参数
    config = {
        'host': '127.0.0.1',
        'port': 3306,
        'user': 'root',
        'passwd': 'root',
        'charset': 'utf8',
        'cursorclass': pymysql.cursors.DictCursor
    }

    # 初始化打开数据库连接
    mydb = MysqldbHelper(config)

    # 打印数据库版本
    print(mydb.getVersion())

    # # 创建数据库
    # DB_NAME = input('输入要创建的数据库名：')
    # mydb.createDataBase(DB_NAME)
    #
    # # 选择数据库
    # print("========= 选择数据库%s ===========" % DB_NAME)
    # mydb.selectDataBase(DB_NAME)
    #
    #创建表
    # TABLE_NAME = input('输入要创建的数据表名：')
    # print("========= 选择数据表%s ===========" % TABLE_NAME)
    # '''例如
    #     CREATE TABLE `lisi` (
    #       `id` bigint(11) NOT NULL auto_increment,
    #       `name` varchar(30) NOT NULL,
    #       PRIMARY KEY  (`id`)
    #     ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
    # '''
    # print("========= 设置表的字段和属性 ===========" )
    # attrdict = {
    #     'name':'varchar(30) NOT NULL'
    # }
    # constraint = "PRIMARY KEY(`id`)"
    # mydb.creatTable(TABLE_NAME,attrdict,constraint)
    # print('首次创建以后，请手动刷新一下数据库表页面。')

    # # 插入纪录
    # print("========= 单条数据插入 ===========")
    # params = {}
    # for i in range(5):
    #     params.update({"name":"testuser"+str(i)}) # 生成字典数据，循环插入
    #     print(params)
    #     mydb.insert(TABLE_NAME, params)
    #     print("")
    #
    # # 批量插入数据
    # print("========= 多条数据同时插入 ===========")
    # insert_values = []
    # for i in range(5):
    #     # values.append((i,"testuser"+str(i)))
    #     insert_values.append([u"测试用户"+str(i)]) # 插入中文数据
    # print(insert_values)
    # insert_attrs = ["name"]
    # mydb.insertMany(TABLE_NAME,insert_attrs, insert_values)
    #
    # # 数据查询
    # print("========= 数据查询 ===========")
    # print(mydb.select(TABLE_NAME, fields=["id", "name"]))
    # print(mydb.select(TABLE_NAME, cond_dict = {'name':'测试用户1'},fields=["id", "name"]))
    # print(mydb.select(TABLE_NAME, cond_dict = {'name':'测试用户2'},fields=["id", "name"],order="order by id desc"))
    #
    # # 删除数据
    # print("========= 删除数据 ===========")
    # delete_params = {"name": "测试用户2"}
    # mydb.delete(TABLE_NAME, delete_params)
    #
    # # 更新数据
    # print("========= 更新数据 ===========")
    # update_params = {"name": "测试用户99"}   # 需要更新为什么值
    # update_cond_dict = {"name": "测试用户3"}  # 更新执行的查询条件
    # mydb.update(TABLE_NAME, update_params, update_cond_dict)
    #
    # # 删除表数据
    # print("========= 删除表数据 ===========")
    # mydb.deleteTable(TABLE_NAME)
    #
    # # 删除表
    # print("========= 删除表===================")
    # mydb.dropTable(TABLE_NAME)
    #