This kind of code perhaps should work for You SELECT *, CASE WHEN (pvc IS NULL OR pvc = '') AND (datepose < 1980) THEN '01' WHEN (pvc IS NULL OR pvc ... ... <看更多>

--- A Postgres case statement is a conditional statement similar to if/else statements in other programming ... ... <看更多>

There are several problems with your query. First of all you use single quotes which makes query invalid. Postgres will interpret strings ... ... <看更多>