Sql NULLIF()函数不使用';不能使用WHERE子句
以下查询的实际结果为空Sql NULLIF()函数不使用';不能使用WHERE子句,sql,sql-server-2008,Sql,Sql Server 2008,以下查询的实际结果为空 select semid from programvariantterm where programvariantid = 240 但当我尝试以下语句时,它给出0行: declare @semid int set @semid = -1 select semid from programvariantterm where programvariantid = 240 and semid = nullif(@semid,-1) 我觉得你有点把NULLIF和ISNULL
select semid from programvariantterm where programvariantid = 240
但当我尝试以下语句时,它给出0行:
declare @semid int
set @semid = -1
select semid from programvariantterm
where programvariantid = 240 and semid = nullif(@semid,-1)
我觉得你有点把
NULLIF
和ISNULL
搞混了
您的语句将使用以下ISNULL
:
where programvariantid = 240 and @semid = ISNULL(semid,-1)