Create a constant in Postgresql

Question

Suppose that I have this query:

select * 
from myTable
where myTable.myCol in (1,2,3)

I would like to do that:

with allowed_values as (1,2,3)
select * 
from myTable
where myTable.myCol in allowed_values

It gives me a Syntax Error in the first row, can you help me fixing it?

Answer 1

The closest I can think to your syntax:

WITH allowed_values (id) AS 
  ( VALUES
      (1), (2), (3)
  )
SELECT * 
FROM myTable
WHERE id IN 
   (TABLE allowed_values) ;

Tested in SQL-Fiddle