Thanks so much for your reply. For information, i try to do with Postgis the union Qgis Geoprocessing : https://docs.qgis.org/3.40/en/docs/user_manual/processing_algs/qgis/vectoroverlay.html#union
Le mar. 24 juin 2025 à 12:11, Darafei "Komяpa" Praliaskouski <[email protected]> a écrit : > Hello, > > I am not sure what you wanted to do, but the query you wrote runs union > pairwise between all objects of the first table and second table, creating > NxM objects each of which is a sum of two different polygons in the first > and second layer. It is entirely possible that this consumes all of your > disk drive and then frees it back up during crash handling. Please get > someone to write the query to correctly do what you meant to do instead. > > On Tue, Jun 24, 2025 at 12:37 PM celati Laurent <[email protected]> > wrote: > >> <https://gis.stackexchange.com/posts/494155/timeline> >> >> Dear all, >> >> I want to compare a geoprocessing done in QGIS and PostGIS. It involves a >> union of two large polygonal vector layers.The processing in QGIS tooks 1.5 >> hours on a well-equipped workstation (32 GB of RAM). I was never able to >> complete the processing on PostGIS. >> >> Here is the tested SQL query: >> >>> create table public.union as select st_union(ST_Forece2D(mos.geom), >>> ST_Forece2D(bd_topo_bat.geom)) from public.mos, public.bd_topo_bat >> >> Here is the error message: >> >>> ERROR: could not extend file "base/19370/76968.57" with >>> FileFallocate(): No space left on device HINT: Check available disk >>> space. ERROR: Could not extend file "base/19370/76968.57" with >>> FileFallocate(): No space left on device SQL state: 53100 >> >> The error message is related to a problem with the temporary log file. In >> the postgresql.conf file, I edited the file by setting the value of >> log_temp_files = 10240. The default value was -1. I took this action based >> on this post: >> https://stackoverflow.com/questions/50833992/postgresql-no-space-left-on-device >> Thanks so much. >> >
