[gdal-dev] GDAL may create slow GPKG/SQLite indexes

[Jukka Rahkonen]

Even Rouault <even.rouault <at> mines-paris.org> writes:

> 
> Jukka,
> 
> I tried to simulate your scenario but couldn't observe any performance 
> difference (on Linux, but I doubt that the OS would make a difference) when 
> generating a test DB with 3.7.9 or 3.7.14, and using it with the other 
> version.
> However it might heavily depend on the number of records that match 
> attr_1='009' and area>1000
> 
> Could you share your DB ?

Hi,

I created a new one for you. It was a bit irritating job because the speed
test results are not at all stable. I suppose that same cachign may occur
here and there. However, this one in now very slow (for example 500 seconds)
with OpenJUMP which reads data from java through sqlite-jdbc-3.7.2.jar. Same
query from ogrinfo tends to take around 25 s and when I made a copy of the
db, dropped and created indexes again with spatialite-gui the query takes
about 0.2 s. However, this procedure did not make ogrinfo faster. Running
ANALYZE and VACUUM did not make a big difference for me.

select * from indextest
where knro='781'
or pinta_ala>1000;

http://hip.latuviitta.org/tiedostot/indextest.zip


-Jukka Rahkonen-