如何检查SQL Server 2012的IF-ELSE控制语句中是否已成功执行SQL查询？

Question

I am storing department name in a variable @department which I will be fetching from a row now for that particular department name I want to find out whether a department id exists or not in departments table means whether the department name entered by the user is a valid department or not. How to do this? How do I turn this query into a boolean expression?

create table dbo.departments
(
    department_id int primary key;
    department_name varchar(255);
)

if(select @finaldepartment_id = department_id 
   from dbo.departments 
   where department_name like @department)
   set @department_flag = 1;
else
   set @department_flag = 0;

Answer 1

It can be simplified to single query

SET @department_flag = CASE 
                         WHEN EXISTS (SELECT 1 
                                      FROM   dbo.departments 
                                      WHERE  department_name LIKE Concat('%',@department,'%')) THEN 1
                         ELSE 0 
                       END 

Answer 2

To check if there is any department that matches your condition use EXISTS

IF EXISTS (
  select 1 
  from dbo.departments 
  where department_name like '%'+@department+'%'
  )

If you need to assign an id from departments into a variable, set the variable with the result and then check if it's not null.