Resolved get altenate data if there is no demanded data

[BubikolRamios]

data, for 'en' there is always data.

1   en   dog
1   sl    pes
2   en   peacock
....

1.get all for 'it' from that data, and if it does not exist get 'en' -->
1 dog
2 peacock

2.get all for 'sl' from that data, and if it does not exist get 'en'-->
1 pes
2 peacock

query that would do all that provided one parameter 'en','it',or 'sl', or any other language ?

[Old Pedant]

Hmmm...a fun one!

First thing I would try off the top of my head (UNTESTED!) would be

SELECT W.id, IF( SL.id IS NULL, W.word, SL.word ) AS TheWord
FROM words AS W 
LEFT JOIN ( SELECT id, language, word FROM words WHERE language = 'sl' ) AS SL
ON W.id = SL.id
WHERE W.id IN ( 1, 2 )

Again, untested (I don't have MYSQL on this machine...don't ask why not), but feels right.

[BubikolRamios]

excelent !

small correction:

SELECT W.id, IF( SL.id IS NULL, W.word, SL.word ) AS TheWord
FROM words AS W 
LEFT JOIN ( SELECT id, language, word FROM words WHERE language = 'sl' ) AS SL
ON W.id = SL.id
WHERE W.language = 'en'

PS

Lately I 'm writing qustions that nobody knows the answer, or ..... are fun (-:

Glad that there are people outthere finding my questions interesting.

[Old Pedant]

Whoops...nice catch on the need for the WHERE clause there.

Well, I did say it was untested. Sorry!