Define user variables to use in a SQL that has an "in" statement in MySQL Workbench

Question

I am trying to use defined variables in MySQL Workbench. I am using version 6.3 of Workbench. I am trying to run ad hoc queries that can have a value or multiple values:

If I have a single value, the query runs okay

set @Zdept_Id="548"

and then

Select *
from employees
where dept_Id in (@ZDept_Id)

but if I want to execute this for multiple departments, the query only returns values for the first number

set @Zdept_Id="548,221,1973,905"

and then

Select *
from employees
where dept_Id in (@ZDept_Id)

Dept_Id is an integer.

PS. These are reports that I run once a month, so automating them is not an option due to cost/benefit.

Answer 1

I hope you are looking for FIND_IN_SET().

SELECT *
FROM employees 
WHERE FIND_IN_SET(dept_Id, @ZDept_Id);