I am working on electronic dictionary database in mysql. And i want to select data where some field is null.

Picture for final results:

Final results

Picture of my db:

Database scheme

I was trying to select it like this:

SELECT ot.term AS O_TERM, tt.term AS T_TERM, u.username AS USER_APP
FROM original_language ol, translation_language tl, original_term ot, translation_term tt, user_app u, translation t
WHERE ol.id = ot.original_language_id
AND tl.id = tt.translation_language_id
AND t.original_language_id = ot.id
AND t.translation_language_id = tt.id
AND t.user_id = u.id
AND ol.name = 'english' -- original language (left column)
AND tl.name = 'montenegrian' -- translation language (right column)

0 Answers