How do I cast a string to integer and have 0 in case of error in the cast with PostgreSQL?

Question

In PostgreSQL I have a table with a varchar column. The data is supposed to be integers and I need it in integer type in a query. Some values are empty strings. The followin

Answer 1

I also have the same need but that works with JPA 2.0 and Hibernate 5.0.2:

SELECT p FROM MatchProfile p WHERE CONCAT(p.id, '') = :keyword

Works wonders. I think it works with LIKE too.