On Thu, Jul 10, 2014 at 06:38:26PM -0400, Bruce Momjian wrote: > On Thu, Jul 10, 2014 at 06:17:14PM -0400, Bruce Momjian wrote: > > Well, we are going to need to call internal C functions, often bypassing > > their typical call sites and the assumption about locking, etc. Perhaps > > this could be done from a plpgsql function. We could add and drop a > > dummy column to force TOAST table creation --- we would then only need a > > way to detect if a function _needs_ a TOAST table, which was skipped in > > binary upgrade mode previously. > > > > That might be a minimalistic approach. > > I have thought some more on this. I thought I would need to open > pg_class in C and do complex backend stuff, but I now realize I can do > it from libpq, and just call ALTER TABLE and I think that always > auto-checks if a TOAST table is needed. All I have to do is query > pg_class from libpq, then construct ALTER TABLE commands for each item, > and it will optionally create the TOAST table if needed. I just have to > use a no-op ALTER TABLE command, like SET STATISTICS. > > I am in Asia the next two weeks but will work on it after I return.
Attached is the backend part of the patch. I will work on the pg_upgrade/libpq/ALTER TABLE part later. -- Bruce Momjian <br...@momjian.us> http://momjian.us EnterpriseDB http://enterprisedb.com + Everyone has their own god. +
diff --git a/src/backend/catalog/toasting.c b/src/backend/catalog/toasting.c new file mode 100644 index bdfeb90..6e8ef36 *** a/src/backend/catalog/toasting.c --- b/src/backend/catalog/toasting.c *************** create_toast_table(Relation rel, Oid toa *** 165,180 **** if (rel->rd_rel->reltoastrelid != InvalidOid) return false; ! /* ! * Check to see whether the table actually needs a TOAST table. ! * ! * If an update-in-place toast relfilenode is specified, force toast file ! * creation even if it seems not to need one. ! */ ! if (!needs_toast_table(rel) && ! (!IsBinaryUpgrade || ! !OidIsValid(binary_upgrade_next_toast_pg_class_oid))) ! return false; /* * If requested check lockmode is sufficient. This is a cross check in --- 165,211 ---- if (rel->rd_rel->reltoastrelid != InvalidOid) return false; ! if (!IsBinaryUpgrade) ! { ! if (!needs_toast_table(rel)) ! return false; ! } ! else ! { ! /* ! * Check to see whether the table needs a TOAST table. ! * ! * If an update-in-place TOAST relfilenode is specified, force TOAST file ! * creation even if it seems not to need one. This handles the case ! * where the old cluster needed a TOAST table but the new cluster ! * would not normally create one. ! */ ! ! /* ! * If a TOAST oid is not specified, skip TOAST creation as we will do ! * it later so we don't create a TOAST table whose OID later conflicts ! * with a user-supplied OID. This handles cases where the old cluster ! * didn't need a TOAST table, but the new cluster does. ! */ ! if (!OidIsValid(binary_upgrade_next_toast_pg_class_oid)) ! return false; ! ! /* ! * If a special TOAST value has been passed in, it means we are in ! * cleanup mode --- we are creating needed TOAST tables after all user ! * tables with specified OIDs have been created. We let the system ! * assign a TOAST oid for us. The tables are empty so the missing ! * TOAST tables were not a problem. ! */ ! if (binary_upgrade_next_toast_pg_class_oid == OPTIONALLY_CREATE_TOAST_OID) ! { ! /* clear it so it is no longer used */ ! binary_upgrade_next_toast_pg_class_oid = InvalidOid; ! ! if (!needs_toast_table(rel)) ! return false; ! } ! } /* * If requested check lockmode is sufficient. This is a cross check in diff --git a/src/include/catalog/binary_upgrade.h b/src/include/catalog/binary_upgrade.h new file mode 100644 index f39017c..7aff509 *** a/src/include/catalog/binary_upgrade.h --- b/src/include/catalog/binary_upgrade.h *************** *** 14,19 **** --- 14,22 ---- #ifndef BINARY_UPGRADE_H #define BINARY_UPGRADE_H + /* pick a OID that will never be normally used for TOAST table */ + #define OPTIONALLY_CREATE_TOAST_OID 1 + extern PGDLLIMPORT Oid binary_upgrade_next_pg_type_oid; extern PGDLLIMPORT Oid binary_upgrade_next_array_pg_type_oid; extern PGDLLIMPORT Oid binary_upgrade_next_toast_pg_type_oid;
-- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers