Handling NULLs in PostgreSQL: Alternatives to ISNULL

Learn about effective alternatives to the ISNULL function in PostgreSQL, focusing on COALESCE and CASE statements.

PostgreSQL's approach to NULL values includes functions like COALESCE, which handles multiple inputs:

-- PostgreSQL
SELECT COALESCE(salary, 0) AS salary 
FROM employee;

The CASE statement also provides a method for conditional NULL handling:

-- PostgreSQL
SELECT CASE WHEN salary IS NULL THEN 0 ELSE salary END AS salary 
FROM employee;

FAQ

Why do some SQL databases have ISNULL while PostgreSQL does not?

ISNULL is …

case coalesce employee function functions inputs learn multiple null postgresql salary values