python数据库类

#!/usr/bin/env python
# coding:UTF-8
 
 
"""
@version: python3.x
@author:曹新健
@contact: 617349013@qq.com
@software: PyCharm
@file: dbSql.py
@time: 2018/9/22 17:47
"""
 
import pymysql
import logging
import sys
 
# 加入日志
# 获取logger实例
logger = logging.getLogger("dbSql")
# 指定输出格式
formatter = logging.Formatter('%(asctime)s\
              %(levelname)-8s:%(message)s')
# 文件日志
file_handler = logging.FileHandler("dbSql.log")
file_handler.setFormatter(formatter)
# 控制台日志
console_handler = logging.StreamHandler(sys.stdout)
console_handler.setFormatter(formatter)
 
# 为logge添加具体的日志处理器
logger.addHandler(file_handler)
logger.addHandler(console_handler)
 
logger.setLevel(logging.INFO)
 
 
class DbManager:
    # 构造函数
    def __init__(self, host='127.0.0.1',port=3306, user='cxj',
passwd='123456', db='cxjtest',charset='utf8'):
        self.host = host
        self.port = port
        self.user = user
        self.passwd = passwd
        self.db = db
        self.charset = charset
        self.conn = None
        self.cur = None
 
    # 连接数据库
    def connectDatabase(self):
        try:
            self.conn = pymysql.connect(host=self.host,port=self.port,user=self.user,passwd=self.passwd,db=self.db,charset=self.charset)
        except:
            logger.error("connectDatabase failed")
            return False
        self.cur = self.conn.cursor()
        return True
 
    # 关闭数据库
    def close(self):
        # 如果数据打开,则关闭;否则没有操作
        if self.conn and self.cur:
            self.cur.close()
            self.conn.close()
        return True
 
    # 执行数据库的sq语句,主要用来做插入操作
    def execute(self, sql,params=None,commit=False,):
        # 连接数据库
        res = self.connectDatabase()
        if not res:
            return False
        try:
            if self.conn and self.cur:
                # 正常逻辑,执行sql,提交操作
                rowcount = self.cur.execute(sql, params)
                #print(rowcount)
                if commit:
                    self.conn.commit()
                else:
                    pass
        except:
            logger.error("execute failed: " + sql)
            logger.error("params: " + str(params))
            self.close()
            return False
        return rowcount
 
    # 查询所有数据
    def fetchall(self, sql, params=None):
        res = self.execute(sql, params)
        if not res:
            logger.info("查询失败")
            return False
        self.close()
        results = self.cur.fetchall()
        logger.info("查询成功" + str(results))
        return results
 
     # 查询一条数据
    def fetchone(self, sql, params=None):
        res = self.execute(sql, params)
        if not res:
            logger.info("查询失败")
            return False
        self.close()
        result = self.cur.fetchone()
        logger.info("查询成功" + str(result))
        return result
 
    # 增删改数据
    def edit(self, sql,params=None):
        res = self.execute(sql,params,True)
        if not res:
            logger.info("操作失败")
            return False
        self.conn.commit()
        self.close()
        logger.info("操作成功" + str(res))
        return res
 
 
if __name__ == '__main__':
    dbManager = DbManager()
    """
    sql = "select * from bandcard WHERE money>%s;"
    values = [1000]
    result = dbManager.fetchall(sql, values)
    """
    sql = "insert into bandcard values %s,%s,%s;"
    values = [(0, 100), (0, 200), (0, 300)]
    result = dbManager.edit(sql,values)

import re

import pymysql
"""
connect连接对象的方法:

close()  --关闭的方法

commit()   --如果支持事务则提交挂起的事务

rollback()  --回滚挂起的事务

cursor()  --返回连接的游标对象
游标对象的方法:

callproc(name,[params]) --用来执行存储过程,接收的参数为存储过程的名字和参数列表,返回受影响的行数

close()  --关闭游标

execute(sql,[params])--执行sql语句,可以使用参数,(使用参数时,sql语句中用%s进行站位注值),返回受影响的行数

executemany(sql,params)--执行单挑sql语句,但是重复执行参数列表里的参数,返回受影响的行数

fetchone()  --返回结果的下一行

fetchall()  --返回结果的 所有行

fetchmany(size)--返回size条记录,如果size大于返回结果行的数量,则会返回cursor.arraysize条记录

nextset()  --条至下一行

setinputsizes(size)--定义cursor

游标对象的属性:

description--结果列的描述,只读

rowcount  --结果中的行数,只读

arraysize  --fetchmany返回的行数,默认为1

"""
class MysqldbHelper(object):
    """操作mysql数据库,基本方法

        """
    def __init__(self , host="localhost", username="root", password="", port=3306, database="python_test"):
        self.host = host
        self.username = username
        self.password = password
        self.database = database
        self.port = port
        self.con = None
        self.cur = None
        try:
            self.con = pymysql.connect(host=self.host, user=self.username, passwd=self.password, port=self.port, db=self.database)
            # 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:
            raise "DataBase connect error,please check the db config."

    def close(self):
        """关闭数据库连接

        """
        if not  self.con:
            self.con.close()
        else:
            raise "DataBase doesn't connect,close connectiong error;please check the db config."

    def getVersion(self):
        """获取数据库的版本号

        """
        self.cur.execute("SELECT VERSION()")
        return self.getOneData()

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

    def creatTable(self, tablename, attrdict, constraint):
        """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`)
        """
        if self.isExistTable(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 = 'MySQL execute failed! ERROR (%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 = 'MySQL execute failed! ERROR (%s): %s' %(e.args[0],e.args[1])
            print("error:", error)
            return error

    def insert(self, tablename, params):
        """插入数据库

            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)+')'
        sql = 'insert into %s'%tablename
        sql = sql + attrs_sql + values_sql
        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:
                raise "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
        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__":
    mydb = MysqldbHelper()
    print(mydb.getVersion())
    table='test_mysqldb'
    attrs={'name':'varchar(200) DEFAULT NULL','age':'int(11) DEFAULT NULL'}
    constraint='PRIMARY KEY(`id`)'
    print(mydb.creatTable(table, attrs, constraint))
    params = {"name" : "caixinglong", "age" : "38"}
    mydb.insert('test_mysqldb', params)
    print(mydb.select(table))
    print(mydb.select(table, fields=["name", "age"]))
    print( mydb.select(table, fields=["age", "name"]))
    key = ["id" ,"name", "age"]
    value = [[101, "liuqiao", "25"], [102,"liuqiao1", "26"], [103 ,"liuqiao2", "27"], [108 ,"liuqiao3", "28"]]
    mydb.insertMany(table, key, value)
    mydb.delete(table, params)
    cond_dict = {"name" : "liuqiao", "age" : "18"}
    mydb.update(table, params, cond_dict)
    # mydb.deleteTable(table)
    # mydb.dropTable(table)
    print(mydb.select(table+ "1"))
    print( mydb.isExistTable(table+ "1"))


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