[MapServer-users] How to avoid writing empty tiles with mapcache_seed

[Johannes Paul]

Hi Philippe,
by using <detect_blank/> you can store a quadruplet of the rgba color in
the data blob instead of the compressed image data, it should then be easy
to get rid of these tiles in the SQLite if needed (DELETE FROM tiles WHERE
length(tile_data) = 4;).
https://mapserver.org/mapcache/caches.html#blank-tile-detection
Johannes

On Thu, 26 Mar 2026 at 08:49, Philippe Ghesquiere via MapServer-users <
mapserver-users at lists.osgeo.org> wrote:

>
> Hi all,
>
> While creating a GPKG cache with mapcache_seed, I would like to avoid
> writing empty tiles.
> I know that <symlink/> can save disk space. But I would like to get rid of
> these empty tiles.
> Is there any parameter to achieve it ?
>
> If there is no such parameter, do you have any idea for some post-process
> SQLITE command to remove these tiles ?
>
> Thanks for your help
> Philippe
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