Function alias for Postgres default function

Question

I always use NVL() for assigning a default value when the result is null.

However in PostgreSql there is only COALESCE().

Can I give the COALESCE function an alias so it executes with NVL?

Or can I copy the function declaration somehow?

Answer 1

You can use this wrapper:

create or replace function nvl (anyelement, anyelement)
returns anyelement language sql as $$
    select coalesce($1, $2)
$$;

See also Oracle Differences between NVL and Coalesce.