insert table1 (username,pwd)values ('myname','mypwd')当table1里存在username=myname,pwd=mypwd记录时就不插入 ----------------- if exists (select * from table1 where username=myname and pwd=mypwd) print '存在' else insert table1 (username,pwd)values ('myname','mypwd')
用存储过程吧 CREATE PRO SP_INSERT @USERNAME VARCHAR(200), @PWD VARCHAR(200) AS IF(@USERNAME<>'myname' OR @PWD<>'mypwd' ) BEGIN insert table1 (username,pwd)values (@USERNAME,@PWD) END
insert table1 (username,pwd) select top 1 'myname','mypwd' from table1 where colname <> 'myname' and colpassword <> 'mypwd'
当table1里存在username=myname,pwd=mypwd记录时就不插入 ---------------------------------------- 如果myname、mypwd是变量的话,一条语句肯定不行if not exists (select * from table1 where username='myname' and pwd='mypwd') insert into table1 (username,pwd)values ('myname','mypwd')
-----------------
if exists (select * from table1 where username=myname and pwd=mypwd)
print '存在'
else insert table1 (username,pwd)values ('myname','mypwd')
CREATE PRO SP_INSERT
@USERNAME VARCHAR(200),
@PWD VARCHAR(200)
AS
IF(@USERNAME<>'myname' OR @PWD<>'mypwd' )
BEGIN
insert table1 (username,pwd)values (@USERNAME,@PWD)
END
select top 1 'myname','mypwd'
from table1
where colname <> 'myname' and colpassword <> 'mypwd'
----------------------------------------
如果myname、mypwd是变量的话,一条语句肯定不行if not exists (select * from table1 where username='myname' and pwd='mypwd')
insert into table1 (username,pwd)values ('myname','mypwd')