Create array in SELECT

Question

I\'m using PostgreSQL 9.1 and I have this data structure:

A     B
-------
1     a
1     a
1     b
1     c
1     c
1     c
1     d
2     e
2     e

Answer 1

Maybe I'm missing something, but this should do it:

SELECT a, 
       count(*) as cnt,
       array_agg(b) as all_values
FROM your_table
GROUP BY a