[DUG] Frebird index question

Rohit Gupta r.gupta at xtra.co.nz
Mon Nov 5 07:27:31 NZDT 2012

Yes, the index creation is immediate. It is most likely that

 1. your query is not using the index (look at the plan)
 2. your index is not specific enough.


 1. If you have two indexes that could be used (looking the where or
    order by clause) then firebird will use the index with the best
    selectivity.  You may have to rebuild the indexes to fix the
    selectivity if its wrong.  Or change your where clause - you put in
    dummy clauses to coax it.
 2. Maybe you need a multi-field index.  Also note that firebird will
    use the fields with fixed (non range/between) values to determine
    the index to use first.

Post your query and the index you are trying to use.


On 29/10/2012 9:26 a.m., John Bird wrote:
> Firebird V2
> I have a large table (5,500,000+ records) that I just added an index 
> to to speed some queries.   So far it has not made much difference -- 
> is the existing data indexed immediately on creating the index?
> John Bird

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