Subject | Re: [firebird-support] Re: SELECT COUNT performance |
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Author | Doug Chamberlin |
Post date | 2010-07-10T13:10:14Z |
On 7/10/2010 8:14 AM, sqlsvr wrote:
What is the SQL used? What is the table schema? What is the selectivity
on the index? How many records in the table?
> Thanks for the response. The resource states:I haven't seen a where clause in this thread yet.
> Reason is that Firebird doesn't keep information about number of records in database. Since query doesn't have WHERE clause, it cannot use index either, and has to go through all the records.
>
> But my query DOES have a where clause (it is an indexed column) and it is very slow.
What is the SQL used? What is the table schema? What is the selectivity
on the index? How many records in the table?