Hi Even, Thanks for the change! I've now tested the GDAL trunk with QGIS and it's lightning fast with large files - problem solved.
Thanks once again, Jeremy ________________________________________ From: Even Rouault [[email protected]] Sent: Saturday, 17 May 2014 10:48 p.m. To: [email protected] Cc: Stefan Keller; Jeremy Palmer Subject: Re: [Qgis-developer] Geospackage Slow in QGIS Le samedi 17 mai 2014 10:46:39, Stefan Keller a écrit : > So it's this code fragment? > 419 /* Requirement 6: The SQLite PRAGMA integrity_check SQL command > SHALL return â??okâ? */ > 420 /* http://opengis.github.io/geopackage/#_file_integrity */ > 421 if( strncmp(pszFilename, "/vsicurl/", strlen("/vsicurl/")) != 0 && > 422 OGRERR_NONE != PragmaCheck("integrity_check", "ok", 1) ) > > Looks strange to me why a single file check woold be the bottlenet since > this should be a single call. > > I would have expected that some repeated calls (like reading > objects/records and checking SRID or data types) would be the bottleneck > since SQlite is not performant when used with PRAGMA checks. This would be > a check one could disable with a parameter. I've just noticed that thread. Actually I found that integrity_check was slow when operating on remote databases with /vsicurl/ and didn't verify how slow it could be with local big files, but its documentation at http://www.sqlite.org/pragma.html#pragma_integrity_check suggests that it might be bery slow indeed. Reading the GeoPackage spec, nothing mandates to do the integrity_check at open time. It only mandates that if you run "pragma integrity_check" it should retrun OK. So I've disabled the check by default. Even -- Geospatial professional services http://even.rouault.free.fr/services.html This message contains information, which may be in confidence and may be subject to legal privilege. If you are not the intended recipient, you must not peruse, use, disseminate, distribute or copy this message. If you have received this message in error, please notify us immediately (Phone 0800 665 463 or [email protected]) and destroy the original message. LINZ accepts no responsibility for changes to this email, or for any attachments, after its transmission from LINZ. Thank You. _______________________________________________ Qgis-developer mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/qgis-developer
