On Fri, Oct 18, 2013 at 9:12 PM, Tom Lane <tgl@xxxxxxxxxxxxx> wrote:
dinesh kumar <dineshkumar02@xxxxxxxxx> writes:ANALYZE normally collects statistics about the contents of table columns.
> When we create an index, i believe the postgres engine it self update it's
> catalog about the index availability.
Thus, adding (or removing) an index does not create any reason to
re-ANALYZE.
However ... if you have an index on an _expression_ (not just a simple
column value), that cues ANALYZE to collect statistics about the values of
that _expression_. So re-analyzing is useful after creating such an index,
to give the planner a better idea of when to use that index.
Thank you Tom.
Whether you used CREATE INDEX CONCURRENTLY or some other way of creating
the index doesn't matter at all.
regards, tom lane
Regards,
Dinesh
