Re: why group expressions cause query to run forever

> I think the problem is probably that you're sorting two dozen CHAR
> columns, and that in many of the rows all these entries are '' forcing
> the sort code to compare all two dozen columns (not so)?

Yes, most of columns return empty strings.

I changed empty strings to null, casted to varchar and simplyfied the
statment.
However, this select statement runs forever.

Any idea how to speed it up ?

Andrus.

SELECT
bilkaib.DB,
CASE WHEN dbkonto.objekt1='+' THEN bilkaib.DBOBJEKT ELSE null
END::VARCHAR(10) AS dbobjekt,
CASE WHEN dbkonto.objekt2='+' THEN bilkaib.DB2OBJEKT ELSE null
END::VARCHAR(10) AS db2objekt,
CASE WHEN dbkonto.objekt3='+' THEN bilkaib.DB3OBJEKT ELSE null
END::VARCHAR(10) AS db3objekt,
CASE WHEN dbkonto.objekt4='+' THEN bilkaib.DB4OBJEKT ELSE null
END::VARCHAR(10) AS db4objekt,
CASE WHEN dbkonto.objekt5='+' THEN bilkaib.DB5OBJEKT ELSE null
END::VARCHAR(10) AS db5objekt,
CASE WHEN dbkonto.objekt6='+' THEN bilkaib.DB6OBJEKT ELSE null
END::VARCHAR(10) AS db6objekt,
CASE WHEN dbkonto.objekt7='+' THEN bilkaib.DB7OBJEKT ELSE null
END::VARCHAR(10) AS db7objekt,
CASE WHEN dbkonto.objekt8='+' THEN bilkaib.DB8OBJEKT ELSE null
END::VARCHAR(10) AS db8objekt,
CASE WHEN dbkonto.objekt9='+' THEN bilkaib.DB9OBJEKT ELSE null
END::VARCHAR(10) AS db9objekt
from BILKAIB join KONTO CRKONTO ON bilkaib.cr=crkonto.kontonr
join KONTO DBKONTO ON bilkaib.db=dbkonto.kontonr
where
bilkaib.kuupaev BETWEEN '2006-01-01' AND '2006-12-31'
GROUP BY 1,2,3,4,5,6,7,8,9,10