In many cases, you need to use multiple parameters to query a temporary table. Each parameter requires different result sets. Some parameters do not correspond to fields in this temporary table, but to fields in another table associated with the temporary table ID.
In many cases, you need to use multiple parameters to query a temporary table. Each parameter requires different result sets. Some parameters do not correspond to fields in this temporary table, but to fields in another table associated with the temporary table ID.
When I write the following SQL statement, I get the result set that I want to input the @ c parameter.
Select * from @ tb t where t. id in (select id from tb where f = @ c)
However, if there are @ a, @ B, and @ c, and they respectively want to get different result sets from @ tb, for example
The Code is as follows:
If @ a is not null
Begin
-- Get What @ a wants
End
If @ B is not null
Begin
-- Get What @ B wants
End
If @ c is not null
Begin
-- Get What @ c wants
End
It seems that there is no problem, but if @ a and @ B are together, or even @ a, @ B, @ c, @ d, @ e, @ f and so on. Therefore, you must build @ tb first and then perform one-time query.
-- Construct @ tb
Select * from @ tb
If I have passed @ a and @ B to get a @ tb result set, when I use @ c again for conditional judgment, the result will be overwritten.
You can use the "delete records that do not meet the conditions" method. Because @ tb has obtained the results @ a and @ B, therefore, you only need to delete the results that do not match @ c. .
The Code is as follows:
If @ c is not null
Begin
Delete c from @ tb c where c. id not in (select id from tb where f = @ c)
End
Select * from @ tb
