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TQuery's and secondary indexes?

there are no index properties for a TQuery and I was wondering as to how effective the BDE is at
taking advantage of secondary indexes. Is it something that one is supposed to specify in the SQL?

Thanks for any help

--

Greg Lorriman co. inc. & sons Ltd

 

Re:TQuery's and secondary indexes?


I copied this from the Paradox 7 online help

'In Paradox tables, a secondary index defines an alternate view order to temporarily change the
display order of the records. The physical location of the records in the table does not change.

Secondary indexes are also used for queries, to speed performance, and to establish links between
tables. '

Paradox automatically takes advantage of a secondary index. It is is a non-maintained index you might
have to wait for the BDE to update the index

I hope this helps you

Greg Lorriman skrev:

Quote
> there are no index properties for a TQuery and I was wondering as to how effective the BDE is at
> taking advantage of secondary indexes. Is it something that one is supposed to specify in the SQL?

> Thanks for any help

> --

> Greg Lorriman co. inc. & sons Ltd

Re:TQuery's and secondary indexes?


In message <34F2F43B.3C8E0...@soelleroed.mail.telia.com> - Michael Juul Hansen

Quote
<m...@soelleroed.mail.telia.com> writes:

>'In Paradox tables, a secondary index defines an alternate view order to temporarily change the
>display order of the records. The physical location of the records in the table does not change.

>Secondary indexes are also used for queries, to speed performance, and to establish links between
>tables. '

This may work for Paradox, but how does it work in Delphi's SQL?
If I add 'ORDER BY fieldname', the SQL interpreter will never know that there
is a secondary index on that fieldname also. Or am I missing something here?

Bye,
Jan

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