python操作mysql——mysql.connector

先安裝 pip， python 的包管理工具

 

安裝

sudo pip install mysql-connector-python

 

連接數據庫

#!/usr/bin/python
# -*- coding: UTF-8 -*-
import mysql.connector

db = mysql.connector.connect(
    host = '127.0.0.1',
    port = 3306,
    user = 'root',
    passwd = 'gou110422',
    database = 'test',
    charset = 'utf8'
)
cursor = db.cursor()

sql_query = 'select name,money from user;'
#執行sql 語句
cursor.execute(sql_query)
print cursor.rowcount
rs = cursor.fetchall()
#cursor.rowcount 表中受影響數據個數
#fetchall() 獲取所有數據
#fetchone()  獲取一條數據
#fetchmany(3) 獲取 3個數據
print rs
for item in rs:
    print 'name: %s  money: %s' % item
print '成功'
#cursor.close() #關閉游標
db.close()

api:http://www.runoob.com/python3/python-mysql-connector.html

示例：

# -*- coding: UTF-8 -*-
import mysql.connector

class TransferMoney():
    def __init__(self, db):
        self.db = db
    #轉賬流程
    def transferMoney(self, id, targetId, money):
        try:
            self.checkTargetUser(targetId) #檢查被轉賬賬號是否存在
            self.checkMoney(id, money) #檢查余額是否足夠
            self.transfer(id, targetId, money) #轉賬
            self.db.commit() #提交修改
        except Exception as e:
            self.db.rollback() #回滾事物
            raise e
    #檢查被轉賬賬號是否存在
    def checkTargetUser(self, id):
        try:
            cursor = self.db.cursor()
            sql_query = 'select * from user where id=%s;' % id
            cursor.execute(sql_query)
            rs = cursor.fetchall()
            if len(rs) != 1:
                raise Exception('轉賬賬戶不存在！')
            else:
               print '轉賬賬戶存在!'
        except mysql.connector.Error as e:
            raise Exception('檢查被轉賬賬戶是否存在出錯：' + str(e))
        finally:
            cursor.close()
    #檢查轉賬金額
    def checkMoney(self, id, money):
        try:
            cursor = self.db.cursor()
            sql_query = 'select * from user where id=%s and money > %s;' % (id,money)
            cursor.execute(sql_query)
            rs = cursor.fetchall()
            if len(rs) != 1:
                raise Exception('轉賬賬戶余額不足！')
            else:
               print '轉賬方金額充足!' 
        except mysql.connector.Error as e:
            raise Exception('檢查金額出錯：：' + str(e))
        finally:
            cursor.close()
    #轉賬
    def transfer(self, id, targetId, money):
        try:
            cursor = self.db.cursor()
            #自己先減去轉賬金額
            sql_query = 'update user set money=money-%s where id=%s;' % (money,id)
            rs = cursor.execute(sql_query)
            if cursor.rowcount != 1:
                raise Exception('賬號%s減款失敗！' % id)
            #目標賬戶加上轉賬金額
            sql_query1 = 'update user set money=money+%s where id=%s;' % (money, targetId)
            cursor.execute(sql_query1)
            if cursor.rowcount != 1:
                raise Exception('賬號%s加款失敗！' % targetId)
            print '成功轉賬%s元！' %  money
        except mysql.connector.Error as e:
            raise Exception('轉賬出錯：' + str(e))
        finally:
            cursor.close()

if __name__ ==  '__main__':
    db = mysql.connector.connect(host='127.0.0.1',port=3306,user='root',passwd='gou110422',database='test',charset='utf8')
    base = TransferMoney(db)
    try:
        id,targetId,money = (1,2,100)
        base.transferMoney(id, targetId, money)
    except Exception as e:
        print '異常：',e
    finally:
        db.close()
#cursor.execute執行sql 語句
#cursor.rowcount 表中受影響數據個數 放在execute()之后
#fetchall() 獲取所有數據
#fetchone()  獲取一條數據
#fetchmany(3) 獲取 3個數據
#db.commit() 數據表內容有更新，必須使用到該語句
#cursor.close() #關閉游標