Postgresql: Matching Patterns between Two Columns

Question

I have two columns say Main and Sub. (they can be of same table or not).

Main is varchar of length 20 and Sub is

Answer 1

Try

SELECT t1.* from "Main Table" AS t1, "SubTable" AS t2
 WHERE t2.SubId=1043
   AND substr(t1.MainColumn, 13, 8) LIKE "%" || CAST(t2.SubColumn as text);