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Thu, Dec 17 2009 8:03 AM	Permanent Link
Uli Becker	Hi, "select * from buchungen order by buchungsdatum desc" takes 1.2 seconds to filter about 11,000 from 40,000 records. "select * from buchungen order by buchungsdatum" needs just 0.1 seconds. Does the descending order prevent the query from using the index on "buchungsdatum"? Uli
Thu, Dec 17 2009 8:34 AM	Permanent Link
Roy Lambert NLH Associates Team Elevate	Uli >needs just 0.1 seconds. Does the descending order prevent the query from >using the index on "buchungsdatum"? Quick answer - yes. Just as in DBISAM indices in ElevateDB are unidirectional. There's also the added complication of collation. You need to make sure everything matches for an index to be of use. Roy Lambert [Team Elevate]
Thu, Dec 17 2009 9:42 AM	Permanent Link
Uli Becker	Roy, > Just as in DBISAM indices in ElevateDB are unidirectional. There's also the added complication of collation. You need to make sure everything matches for an index to be of use. Thanks. So I'll try to create two indexes, one asc and one desc. Any reason why that shouldn't work? Uli
Thu, Dec 17 2009 12:40 PM	Permanent Link
Roy Lambert NLH Associates Team Elevate	Uli >Thanks. So I'll try to create two indexes, one asc and one desc. Any >reason why that shouldn't work? Not that I know of, but if I'm wrong I'm sure someone will tell us. Roy Lambert [Team Elevate]