[postgis-users] Is my query planner failing me, or vice versa?

[Jessica M Salmon]

strk,

                                         postgis_full_version
------------------------------------------------------------------------------------------------------
 POSTGIS="1.0.2" GEOS="2.1.3" PROJ="Rel. 4.4.9, 29 Oct 2004" USE_STATS
DBPROC="0.3.0" RELPROC="0.3.0"

GeomUnion is a major component of the trigger function, but it only is used
when the query has a result (fires grow together). Such is not the case for
any of the explain analyze output shown in the chart. I do have some
massively complex geometries, indeed, but the geometry complexity itself
does not appear to account for the occasionally much-slower-than-expected
queries. Would the filter on the Distance function have the same
unpredictability (in terms of speed) as GeomUnion?

-Meghan



                                                                           
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             12/13/2005 03:44                                      Subject 
             PM                        Re: [postgis-users] Is my query     
                                       planner failing me, or vice versa?  
                                                                           
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Jessica,
the query plan sounds good to me, if it is performance
differences that hit your attention I guess they are due
to GeomUnion operating on differently complex geometries.

If you can handle to isolate the input geometries of
the slow operation that would help further analisys.

Also, telling us GEOS version (postgis_full_version())
would be helpful.

--strk;
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