Hi,
one customer reported an issue related probably to pg_restore and dictionary format.
Inside PostgreSQL 11 I created one large object
I used pg_dump (version 11) and did dump a) dictionary format, b) tar format
I will try to restore these files in PostgreSQL 18 with pg_restore (version 18).
pavel@nemesis:~$ /usr/local/pgsql/master/bin/pg_restore -Ft testx.tar -l
;
; Archive created at 2025-06-08 14:14:08 CEST
; dbname: postgres
; TOC Entries: 7
; Compression: none
; Dump Version: 1.13-0
; Format: TAR
; Integer: 4 bytes
; Offset: 8 bytes
; Dumped from database version: 11.22
; Dumped by pg_dump version: 11.22
;
;
; Selected TOC Entries:
;
4034; 2613 16386 BLOB - 16386 pavel
4035; 0 0 BLOBS - BLOBS
pavel@nemesis:~$ /usr/local/pgsql/master/bin/pg_restore -Fd testx -l
;
; Archive created at 2025-06-08 14:14:16 CEST
; dbname: postgres
; TOC Entries: 7
; Compression: gzip
; Dump Version: 1.13-0
; Format: DIRECTORY
; Integer: 4 bytes
; Offset: 8 bytes
; Dumped from database version: 11.22
; Dumped by pg_dump version: 11.22
;
;
; Selected TOC Entries:
;
4034; 2613 16386 BLOB - 16386 pavel
4035; 0 0 BLOBS - BLOBS
the --list options without problems
When I try to restore blobs
using tar format (b) it is working without problems
but import from dictionary format fails with an error
pavel@nemesis:~$ LANG=C /usr/local/pgsql/master/bin/pg_restore -Fd testx -d postgres
pg_restore: error: could not open large object TOC file "testx/4035.dat" for input: No such file or directory
When I use a dump in dictionary format from pg 18, there is difference
instead of the blobs_4035.toc I have a file blobs.toc with the same content.
In the tar format, the differences between format pg18 and pg11 are the same as in dictionary format, but pg_restore is able to read it correctly.
Probably it is not a critical bug, but it is very confusing for users, and when it is working in tar format, then probably it should work in dictionary format too.
Regards
Pavel
