sql

Question

我将多个插入查询合并到一个查询中（比如combine1.sql）

--insert query 1
--insert query 2
.
.
.
Declare @Tbl_Id INT
Select @Tbl_Id = Id from students where Code='123'
--null value comes in @Tbl_Id
insert into mappingtable values(@Tbl_Id, getdate())

.
.
.
--insert query n

当我执行@Tbl_Id时，我在combine1.sql中获得空值， 但是，当我执行

时

    Declare @Tbl_Id INT
    Select @Tbl_Id = Id from students where Code='123'
    --5 comes in @Tbl_Id
    insert into mappingtable values(@Tbl_Id, getdate())

combine1.sql可能出现的问题。任何帮助表示赞赏。

Answer 1

像这样检查@Tbl_Id值的一件事

 Declare @Tbl_Id INT
    Select @Tbl_Id = Id from students where Code='123'
    --5 comes in @Tbl_Id
    if(@Tbl_Id is not null)
    begin
          insert into mappingtable values(@Tbl_Id, getdate())
    end