sql中的速记IF语句

Question

目前我有一个存储过程,它接受一个字符串

@vari as varchar(30)
if @vari is null 
    SELECT * FROM TABLE 
else 
    SELECT * FROM TABLE WHERE col = @vari
endif

是否有任何方法可以内联if语句,从而不会因为1个参数而声明2个选择？

Answer 1

SELECT * FROM TABLE WHERE (@vari is null or col = @vari)