MySQL väljer inte rad med angivet id

Använd en standard join med lämplig where kriterier:

SELECT tbl_climatic.location, tbl_favourablecrops.favCrop 
FROM tbl_climatic join
     tbl_favourablecrops on tbl_climatic._id=tbl_favourablecrops.location_id
WHERE tbl_favourablecrops.location_id=0