When you store large objects, the actual data resides on pg_largeobject table (https://www.postgresql.org/docs/current/catalog-pg-largeobject.html). So your "app" table might not be the only thing to exclude in your dump.
Regards, Priyanka Chatterjee On Wed, May 20, 2026 at 9:18 AM Ertan Küçükoglu <[email protected]> wrote: > Hello, > > I am using PostgreSQL 18.4 x64 on Windows Server 2022. There is a very > small single database in the cluster. > > There are hourly pg_dump backups scheduled and database backup size is > around 10GB. > > command line is like below > pg_dump.exe -p 5432 -U dbuser --exclude-table=app -F p -b -c -f > "hourly.bak" > > When I check the cluster directory size it is 4.1 GB. > > Database has one BLOB saved in a single record and it is 16MB in size and > that is in the "app" table which is excluded from the backup file. > > I didn't understand about 2.5 times bigger backup sizes than the total > cluster size. I do not know what to check either. Is there a way for me to > make the hourly backup size smaller? > > Thanks & Regards, > Ertan >
