On samedi 4 mars 2017 16:26:35 CET Rahkonen Jukka (MML) wrote:
> I saw this changeset https://trac.osgeo.org/gdal/changeset/37594 and started
> to think that how GDAL is reading SQLite db that is in WAL journal mode
> from zip, tar, vsicurl or from non-writeble directory if it is documented
> to be generally not possible http://www.sqlite.org/draft/wal.html?
The official page is at
"5. It is not possible to open read-only WAL databases. The opening process must have write privileges for "-shm" wal-index shared memory file associated with the database, if that file exists, or else write access on the directory containing the database file if the "-shm" file does not exist. "
I'm trying to optimize the speed of
ogrinfo -ro /vsitar/my.tar.gz/my.gpkg
on very large files
(but it turns out to be much more involved, since it requires system records to be contained at the beginning of the file)