From e8cd6f14a26bbecd3d8abcf36235a033cb035678 Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Mon, 29 Jan 2007 23:22:59 +0000
Subject: [PATCH] Add comment noting that hashm_procid in a hash index's
 metapage isn't actually used for anything.

---
 src/backend/access/hash/hashpage.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/backend/access/hash/hashpage.c b/src/backend/access/hash/hashpage.c
index e1cf17b282d..97eb3c379ee 100644
--- a/src/backend/access/hash/hashpage.c
+++ b/src/backend/access/hash/hashpage.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/hash/hashpage.c,v 1.63 2007/01/05 22:19:22 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/hash/hashpage.c,v 1.64 2007/01/29 23:22:59 tgl Exp $
  *
  * NOTES
  *	  Postgres hash pages look like ordinary relation pages.  The opaque
@@ -275,6 +275,11 @@ _hash_metapinit(Relation rel)
 	metap->hashm_bmshift = i + BYTE_TO_BIT;
 	Assert((1 << BMPG_SHIFT(metap)) == (BMPG_MASK(metap) + 1));
 
+	/*
+	 * Label the index with its primary hash support function's OID.  This is
+	 * pretty useless for normal operation (in fact, hashm_procid is not used
+	 * anywhere), but it might be handy for forensic purposes so we keep it.
+	 */
 	metap->hashm_procid = index_getprocid(rel, 1, HASHPROC);
 
 	/*
-- 
GitLab