Left join with default relation

Question

Need to find all words with their Italian translation, if Italian doesn\'t exist, then need with Spanish (default language). I can`t use more than one query, and where e

Answer 1

I'd join the words table on the translations table twice, once for each language:

SELECT    w.id, 
          w.name,
          COALESCE(it.translation, es.translation) AS translation,
          COALESCE(it.language, es.language) AS language
FROM      words w
LEFT JOIN translation it ON w.id = it.word_id AND it.language = 'it'
LEFT JOIN translation es ON w.id = es.word_id AND es.language = 'es'