That is, there are multiple conditions, but it is not necessarily the query for every condition.
For example, there is a structure of table a as follows
ID INT number
Name varchar (10) name
Sex bit gender
If you want to build a stored procedure, query this table, you have to do this to 3 to 3 to meet this particular condition, we can design:
Alter procedure dbo.newselectcommand (@ID int, @ name nvarchar (18), @ sex bit) Asset NoCount ON; SELECT ID, NAME, SEX from a where (id = @ id or @id is null) and (name = @ Name or @name is null) and (sex = @ sex or @sex is null)
In this way, it can be very convenient to do so many cases. Don't construct query strings, which is not safe. Trouble AJQC blog
