[HACKERS] [ patch ] pg_dump: new --custom-fetch-table and--custom-fetch-value parameters

Hello to everybody,

I had a problem with a Postgresql 9.3.5 on 32 bit linux, old 2.6.26 kernel:

Program: pg_dump
Problem: if you have tables with big blob fields and you try to dump them with --inserts you could get errors like
    pg_dump: [archiver (db)] query failed: lost synchronization with server: got message type "D", length 847712348
    pg_dump: [archiver (db)] query was: FETCH 100 FROM _pg_dump_cursor
    or
    pg_dump: [archiver (db)] query failed: ERROR:  out of memory
    DETAIL:  Failed on request of size 1073741823.
    pg_dump: [archiver (db)] query was: FETCH 100 FROM _pg_dump_cursor
    
I have solve it adding two new parameters, --custom-fetch-table and --custom-fetch-value, to fetch less records for the specified table(s).
This does not completely solve the problem, but it helps you to get more chance to be able to dump your database.

    pg_dump --dbname=healthorganizer --username=hor --column-inserts --custom-fetch-table='"tDocumentsFiles"' --custom-fetch-value=25

I haven't tested the documentation: too many problems while building it (also the original version, without my changes; probably I have bogus tools... and too less time to check/try...).

Attached the patches for the master and REL9_6_STABLE.

I hope it will help somebody else.

 

Bye
Andrea
matfanjol@users.sf.net