From b8be5431a2baa2ea4a5140f1a49c3360deb4d64e Mon Sep 17 00:00:00 2001 From: Robert Haas Date: Thu, 2 Jun 2011 13:28:52 -0400 Subject: [PATCH] Avoid creating init fork for unlogged indexes when it already exists. Report by Greg Sabino Mullane, diagnosis and preliminary patch by Andres Freund, corrections by me. --- src/backend/catalog/index.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/src/backend/catalog/index.c b/src/backend/catalog/index.c index a0898e0048..53b4c3c59b 100644 --- a/src/backend/catalog/index.c +++ b/src/backend/catalog/index.c @@ -1741,9 +1741,14 @@ index_build(Relation heapRelation, Assert(PointerIsValid(stats)); /* - * If this is an unlogged index, we need to write out an init fork for it. - */ - if (heapRelation->rd_rel->relpersistence == RELPERSISTENCE_UNLOGGED) + * If this is an unlogged index, we may need to write out an init fork for + * it -- but we must first check whether one already exists. If, for + * example, an unlogged relation is truncated in the transaction that + * created it, or truncated twice in a subsequent transaction, the + * relfilenode won't change, and nothing needs to be done here. + */ + if (heapRelation->rd_rel->relpersistence == RELPERSISTENCE_UNLOGGED + && !smgrexists(indexRelation->rd_smgr, INIT_FORKNUM)) { RegProcedure ambuildempty = indexRelation->rd_am->ambuildempty; -- 2.40.0