SQL数据库如下：

DECLARE @isexist INT--申明变量

            select @isexist=count(*) from Table1  where ip=@ip

            if(@isexist>0)

           update Table1  set ConnTimes=ConnTimes+@ConnTimes,Connecting=@Connecting

           where  ip=@ip

            else

           insert into Table1  (Name,Descriptions,ip,ConnTimes,Connecting)values

           (@Name,@Descriptions,@ip,1,1)

Oracle如下：           

MERGE INTO MM_FREZENDPRESALEORDER T1

USING (SELECT '990000006693' AS ordercode,'a' AS salecode,'b' as warecode,1 as frezenqty  FROM dual) T2

ON ( T1.ordercode=T2.ordercode and T1.warecode=T2.warecode and T1.salecode=T2.salecode)

WHEN MATCHED THEN

    UPDATE SET T1.frezenqty = T1.frezenqty + T2.frezenqty

WHEN NOT MATCHED THEN 

    INSERT (ID,ordercode,warecode,salecode,createdate,frezenqty) VALUES(SYS_GUID(),T2.ordercode,T2.warecode,T2.salecode,sysdate,T2.frezenqty);

最近做MySQL，例子如下：

 insert into  pet_store.logintest(Id, loginName, userName, passWord, createDate, Creator, modifyDate, Modifier, Remark)

            select @Id as Id ,@loginName as loginName,@userName as userName, @passWord as passWord, @createDate as createDate,

            @Creator as Creator,@modifyDate as modifyDate, @Modifier as Modifier, @Remark as Remark from dual 

            on duplicate key update loginName=values(loginName),userName=values(userName),passWord=values(passWord),

            modifyDate=values(modifyDate),Modifier=values(Modifier),Remark=values(Remark)