[Haskelldb-users] GROUP BY and unique

[Henning T. <has...@he...>]

I found the idea of implementing grouping by the 'unique' statement rather
elegant, but its translation is not conform to SQL, isn't it?


     do p <- table Points.points
        r <- project (Points.c << p!Points.c)
        unique
        return r

Is translated to

SELECT C2 C
FROM (SELECT C C2
       FROM POINTS T1
       GROUP BY C2) T1


But the C2 after GROUP BY does not denote a column of a table. It may be 
replaced by C or the GROUP BY may be moved to the outer SELECT statement.