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

This is what you need:

SELECT A, COUNT(*), array_agg(b)
FROM YourTable
GROUP BY A