如何在Sql中的Where子句中设置条件

Question

我想要显示具有多个条件的条件，但是如果任何条件为空或者没有任何值而不是如何在where子句中设置。 例子：

where 
SR.fk_Designation_ID = @pk_Designation_ID 
and SR.fk_SeniorityCategory_ID = @pk_SeniorityCategory_ID 
and SR.IsCurrent_Appointment = 1 and SR.fk_SeparationType_ID is null 
order by Senority_Joining_For_Order,E.Date_Of_Birth 

这里如果@pk_SeniorityCategory_ID是null比我不想包括where子句and SR.fk_SeniorityCategory_ID = @pk_SeniorityCategory_ID条件。

Answer 1

试试这个：

WHERE 
SR.fk_Designation_ID = @pk_Designation_ID 
AND (@pk_SeniorityCategory_ID IS NULL 
    OR 
    SR.fk_SeniorityCategory_ID = @pk_SeniorityCategory_ID) 
AND SR.IsCurrent_Appointment = 1 AND SR.fk_SeparationType_ID IS NULL 
ORDER BY Senority_Joining_For_Order,E.Date_Of_Birth