python入門23 pymssql模塊（python連接sql server增刪改數據 ）

增刪改數據必須connect.commit()才會生效 

回滾函數 connect.rollback()

 

連接數據庫

'''
dinghanhua
sql server增刪改
'''

import pymssql

server = '192.168.1.1'
user = 'user'
password = '111111'
database = 'test'

dbconnect = pymssql.connect(server = server,user = user,password=password,database = database) #連接到數據庫

 

修改數據

dbcursor.execute("update test_student set name =%s where sno =1",'peter pan')
dbcursor.execute("update test_student set name =%s where sno =2",'silina smith')
dbconnect.commit() #增刪改數據后必須commit

 

刪除數據

dbcursor.execute("delete from test_student  where sno =1",'peter pan')
dbconnect.commit() #增刪改數據后必須commit

 

新增數據

dbcursor.execute("insert into test_teacher values(%d,%s,%s)",(2,'xingxing','111111'))
dbconnect.commit() #增刪改數據后必須commit

 

commit多個

dbcursor.execute("insert into test_teacher values(%d,%s,%s)",(6,'xingxing6','111111'))
dbcursor.execute("update test_student set name =%s where sno =2",'peter Panpan')
dbconnect.commit() #提交多個

commit之前，游標再執行select取出的都是未提交的數據

 

rollback()

dbcursor.execute("insert into test_teacher values(%d,%s,%s)",(7,'xingxing7','111111'))
dbconnect.rollback() #回滾
dbcursor.execute("update test_student set name =%s where sno =2",'peter')
dbconnect.commit()  #提交

 

最后關閉連接

dbcursor.close()
dbconnect.close()

 

commit之后數據庫數據已變更，回滾是無效的，必須commit之前回滾。commit之前可以做下判斷。

#避免delete或update未加where語句
with  pymssql.connect(server = server,user = user,password=password,database = database)  as dbconnect:
    with dbconnect.cursor() as dbcursor:
        dbcursor.execute("delete from test_teacher")  #假設忘記加delete
 dbcursor.execute("select count(1) from test_teacher") #查詢下刪除后數據個數 if dbcursor.fetchone()[0] == 0: dbconnect.rollback() #回滾 else: dbconnect.commit()

 

 

 cursor.executemany()

with  pymssql.connect(server = server,user = user,password=password,database = database)  as dbconnect:
    with dbconnect.cursor() as dbcursor:
        dbcursor.executemany("insert into test_teacher values (%s,%s,%s)",
                             [(7,'xx','1'),(8,'yy','2'),(9,'zz','3')])
        dbconnect.commit()

 

with as  替代手工關閉

with  pymssql.connect(server = server,user = user,password=password,database = database)  as dbconnect:
    with dbconnect.cursor(as_dict=True) as dbcursor:

        dbcursor.execute("insert into test_teacher values(%d,%s,%s)",(7,'xingxing7','111111'))
        dbconnect.rollback() #回滾
        dbcursor.execute("update test_student set name =%s where sno =2",'peter234')

        dbcursor.execute("select * from test_student")
        print(dbcursor.fetchall()) #取出的是未提交的數據

        dbconnect.commit()

 

the end！