In message <022c01c2bbbe$c27b0e20$0a02a8c0@seal>, Martijn Tonies
<m.tonies@...> writes

>Hi Pete,
>
>> My post commands are very slow.
>
>Do you mean <somedelphicomponent>.Post or do you mean an
>actual INSERT INTO statement?

Yes, Delphi TIBQuery.post. I stepped through the code until I found the
delay. It's an UPDATE rather than an INSERT.

>> I am selecting records "where status=1", dealing with them, then
>> changing Status to 2. Status is not an indexed field. The SELECT
>

>Does the table have a primary key?

Yes, an autoinc, not directly relevant to this SELECT.

>> command is more complex, there are other "wheres", but no other fields
>> are being changed.
>>
>> Since status has low selectivity - there are about 6 choices, over about
>> 5 million records - then I can guess why there might be a problem
>> (index? record moving out of "where" condition?). But I have no idea
>> what to do about it...
>
>You shouldn't index that field - it's no use.

I was wondering if the SELECT might create it's own index, because of
the WHERE. I certainly haven't done so.

>
>
>With regards,
>
>Martijn Tonies

--
Pete Clark