What is the PostgreSQL equivalent for ISNULL()
SELECT CASE WHEN field IS NULL THEN 'Empty' ELSE field END AS field_aliasOr more idiomatic:
SELECT coalesce(field, 'Empty') AS field_alias
Use COALESCE() instead:
SELECT COALESCE(Field,'Empty') from Table;It functions much like ISNULL, although provides more functionality. Coalesce will return the first non null value in the list. Thus:
SELECT COALESCE(null, null, 5); returns 5, while
SELECT COALESCE(null, 2, 5);returns 2
Coalesce will take a large number of arguments. There is no documented maximum. I tested it will 100 arguments and it succeeded. This should be plenty for the vast majority of situations.
How do I emulate the ISNULL() functionality ?
SELECT (Field IS NULL) FROM ...