Re: Bug in pg_dump/restore -o - Mailing list pgsql-hackers

Tom Lane wrote:
> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> > I think I see the cause.  I created a simple table and then generated
> > the dump.  I found this that the normal table had its COPY data in
> > binary format while the max oid dump was pure ASCII.  My guess is that
> > the max oid dump code isn't calling the right routine to dump its data.
>
> Indeed, the max oid dump code doesn't look like it's been clued at all
> about interoperating with the new pg_dump output code.  It can't just
> intermix commands and data into one string and expect pg_restore to cope.
> Compare what happens in dumpClasses/dumpClasses_nodumpData to what's
> being done in setMaxOid.
>
> Philip, you're probably the best-qualified to fix this, but if you don't
> have time today then I can work on it.  I don't want to delay RC1 for
> this...

I am told this was broken in 7.1 too.

Attached is a diff that shows a possible direction for a solution.  What
I did was instead of doing the COPY myself, I am keeping the temp table
I just created and passing that table name to the standard dump routines
to do the COPY.

One problem is that there is no TableInfo for the table, but I can call
getTables() with the temp table name.  Also, it is a temp table and I am
not sure if it is going to like that.

Anyway, this is not completed code but just a possible solution.

--
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 853-3000
  +  If your life is a hard drive,     |  830 Blythe Avenue
  +  Christ can be your backup.        |  Drexel Hill, Pennsylvania 19026
Index: src/bin/pg_dump/pg_dump.c
===================================================================
RCS file: /cvsroot/pgsql/src/bin/pg_dump/pg_dump.c,v
retrieving revision 1.237
diff -c -r1.237 pg_dump.c
*** src/bin/pg_dump/pg_dump.c    2002/01/11 23:21:55    1.237
--- src/bin/pg_dump/pg_dump.c    2002/01/17 23:35:46
***************
*** 4545,4551 ****
  setMaxOid(Archive *fout)
  {
      PGresult   *res;
-     Oid            max_oid;
      char        sql[1024];

      res = PQexec(g_conn, "CREATE TEMPORARY TABLE pgdump_oid (dummy int4)");
--- 4542,4547 ----
***************
*** 4563,4575 ****
          write_msg(NULL, "could not insert into pgdump_oid table: %s", PQerrorMessage(g_conn));
          exit_nicely();
      }
-     max_oid = PQoidValue(res);
-     if (max_oid == 0)
-     {
-         write_msg(NULL, "inserted invalid oid\n");
-         exit_nicely();
-     }
      PQclear(res);
      res = PQexec(g_conn, "DROP TABLE pgdump_oid;");
      if (!res ||
          PQresultStatus(res) != PGRES_COMMAND_OK)
--- 4559,4577 ----
          write_msg(NULL, "could not insert into pgdump_oid table: %s", PQerrorMessage(g_conn));
          exit_nicely();
      }
      PQclear(res);
+     strcpy(sql, "COPY pgdump_oid WITH OIDS FROM stdin;\n");
+
+             dumpCtx = (DumpContext *) malloc(sizeof(DumpContext));
+             dumpCtx->tblinfo = (TableInfo *) tblinfo;
+             dumpCtx->tblidx = 0;
+             dumpCtx->oids = true;
+
+             dumpFn = dumpClasses_nodumpData;
+
+     ArchiveEntry(fout, "0", "Max OID", "<Init>", NULL, sql, "", "", "",
+                  dumpCtx, dumpFn);
+
      res = PQexec(g_conn, "DROP TABLE pgdump_oid;");
      if (!res ||
          PQresultStatus(res) != PGRES_COMMAND_OK)
***************
*** 4578,4594 ****
          exit_nicely();
      }
      PQclear(res);
-     if (g_verbose)
-         write_msg(NULL, "maximum system oid is %u\n", max_oid);
-     snprintf(sql, 1024,
-              "CREATE TEMPORARY TABLE pgdump_oid (dummy int4);\n"
-              "COPY pgdump_oid WITH OIDS FROM stdin;\n"
-              "%u\t0\n"
-              "\\.\n"
-              "DROP TABLE pgdump_oid;\n",
-              max_oid);
-
-     ArchiveEntry(fout, "0", "Max OID", "<Init>", NULL, sql, "", "", "", NULL, NULL);
  }

  /*
--- 4580,4585 ----