Question

I cannot solve this problem for many hours.
This is my table

t1:

–––––––––––––––––––––––––––––––––––
| id | text   |  lang | transl_id |
–––––––––––––––––––––––––––––––––––
| 1  | first  |  en   |  222      |
–––––––––––––––––––––––––––––––––––
| 2  | second |  de   |  222      |
–––––––––––––––––––––––––––––––––––
| 3  |   jkj  |  de   |  234      |
–––––––––––––––––––––––––––––––––––
| 4  |  89080 |  de   |  235      |
–––––––––––––––––––––––––––––––––––

Here is my query:

SELECT
    transl_id AS property,
    (SELECT text FROM t1 WHERE lang='en') AS value1,
    (SELECT text FROM t1 WHERE lang='de') AS value2,

FROM t1

It returns following table:

–––––––––––––––––––––––––––––––––––
| property  |  value1  |  value2  |
–––––––––––––––––––––––––––––––––––
|    222    |  first   |          |
–––––––––––––––––––––––––––––––––––
|    222    |          |  second  |
–––––––––––––––––––––––––––––––––––
|    234    |  jkj     |          |
–––––––––––––––––––––––––––––––––––
|    235    |  89080   |          |
–––––––––––––––––––––––––––––––––––

Each row has either value1 or value2, never both. Is there a way to group results so that rows with equal values for property field would be in one row? I mean something like this:

–––––––––––––––––––––––––––––––––––
| property  |  value1  |  value2  |
–––––––––––––––––––––––––––––––––––
|    222    |  first   |  second  |
–––––––––––––––––––––––––––––––––––
...

Answer 1

Try this query:

SELECT
    property,
    max(value1) as Value1,
    max(value2) as Value2
FROM 
(
SELECT transl_id AS property,
    CASE when lang = 'en' then text else null end as value1,
    CASE when lang = 'de' then text else null end as value2
FROM t1
) t
GROUP BY property

See this SQLFiddle

Tried adding more values in the table and got the desired result in this SQLFiddle.