Question

I’m having a small trouble since it was a long time ago i studies databases and querys.

For example i’ll have two tables for cd:s, one with data and one with alternative translations.
In the CD-table i have the original language, and it looks something like this

Table for CDs (cds):
id  |  name  | language
-----------------------
1   |  aaa   | en
2   |  bbb   | en
3   |  ccc   | fi

Table for languages (languages):
cd_id | language | name
-----------------------
1     | fi       | AAA
1     | de       | AAACHTUNG
3     | en       | CCC

Now, i want to get all these cd:s in for example german, if there’s no translation made i want it to be in the original language…

Edit:
German = de

Since there’s only one german translation (on CD #1) i want cd 2 & 3 in thier original names.. English and finnish in this case…

How can i do this?

Edit 2:
In this case when i ask for ‘de’ i would get:

AAACHTUNG
bbb
ccc

If i ask for ‘en’ i would get

aaa
bbb
CCC

And so on…

Answer 1

This should do the trick (SQL Fiddle):

select coalesce(l.name, c.name)
from cds c
left join languages l on l.cd_id = c.id
                         and l.language = 'de';