From: Bruce Momjian Date: Wed, 5 Mar 2014 15:43:45 +0000 (-0500) Subject: pg_upgrade: improve C comment about what old/new oids match X-Git-Tag: REL9_4_BETA1~385 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=65b96714118d3919195d2dd47e8d2df23718c7ab;p=thirdparty%2Fpostgresql.git pg_upgrade: improve C comment about what old/new oids match --- diff --git a/contrib/pg_upgrade/pg_upgrade.c b/contrib/pg_upgrade/pg_upgrade.c index b992cadbc50..5e210285060 100644 --- a/contrib/pg_upgrade/pg_upgrade.c +++ b/contrib/pg_upgrade/pg_upgrade.c @@ -15,13 +15,12 @@ * oids are the same between old and new clusters. This is important * because toast oids are stored as toast pointers in user tables. * - * FYI, while pg_class.oid and pg_class.relfilenode are initially the same - * in a cluster, but they can diverge due to CLUSTER, REINDEX, or VACUUM - * FULL. The new cluster will have matching pg_class.oid and - * pg_class.relfilenode values and be based on the old oid value. This can - * cause the old and new pg_class.relfilenode values to differ. In summary, - * old and new pg_class.oid and new pg_class.relfilenode will have the - * same value, and old pg_class.relfilenode might differ. + * While pg_class.oid and pg_class.relfilenode are initially the same + * in a cluster, they can diverge due to CLUSTER, REINDEX, or VACUUM + * FULL. In the new cluster, pg_class.oid and pg_class.relfilenode will + * be the same and will match the old pg_class.oid value. Because of + * this, old/new pg_class.relfilenode values will not match if CLUSTER, + * REINDEX, or VACUUM FULL have been performed in the old cluster. * * We control all assignments of pg_type.oid because these oids are stored * in user composite type values.