From 9c7fb7e6d8d0fdcabbdc32daad2159812e538bd5 Mon Sep 17 00:00:00 2001 From: Peter Geoghegan Date: Fri, 29 Mar 2019 12:29:05 -0700 Subject: [PATCH] Tweak some nbtree-related code comments. --- contrib/amcheck/verify_nbtree.c | 2 +- src/backend/access/nbtree/nbtsearch.c | 3 ++- src/backend/access/nbtree/nbtsort.c | 6 +++--- src/include/access/nbtree.h | 11 +++++------ 4 files changed, 11 insertions(+), 11 deletions(-) diff --git a/contrib/amcheck/verify_nbtree.c b/contrib/amcheck/verify_nbtree.c index 9ecb1999e3..9d5b2e5be6 100644 --- a/contrib/amcheck/verify_nbtree.c +++ b/contrib/amcheck/verify_nbtree.c @@ -1975,7 +1975,7 @@ bt_normalize_tuple(BtreeCheckState *state, IndexTuple itup) /* * Search for itup in index, starting from fast root page. itup must be a * non-pivot tuple. This is only supported with heapkeyspace indexes, since - * we rely on having fully unique keys to find a match with only a signle + * we rely on having fully unique keys to find a match with only a single * visit to a leaf page, barring an interrupted page split, where we may have * to move right. (A concurrent page split is impossible because caller must * be readonly caller.) diff --git a/src/backend/access/nbtree/nbtsearch.c b/src/backend/access/nbtree/nbtsearch.c index 7ed4e01bd3..8a5c6b3f24 100644 --- a/src/backend/access/nbtree/nbtsearch.c +++ b/src/backend/access/nbtree/nbtsearch.c @@ -182,7 +182,8 @@ _bt_search(Relation rel, BTScanInsert key, Buffer *bufP, int access, /* * If we're asked to lock leaf in write mode, but didn't manage to, then - * relock. That may happen when the root page appears to be leaf. + * relock. This should only happen when the root page is a leaf page (and + * the only page in the index other than the metapage). */ if (access == BT_WRITE && page_access == BT_READ) { diff --git a/src/backend/access/nbtree/nbtsort.c b/src/backend/access/nbtree/nbtsort.c index a8a7b79267..14d9545768 100644 --- a/src/backend/access/nbtree/nbtsort.c +++ b/src/backend/access/nbtree/nbtsort.c @@ -835,7 +835,7 @@ _bt_buildadd(BTWriteState *wstate, BTPageState *state, IndexTuple itup) * the limit on the size of tuples inserted on the leaf level by the same * small amount. Enforce the new v4+ limit on the leaf level, and the old * limit on internal levels, since pivot tuples may need to make use of - * the resered space. This should never fail on internal pages. + * the reserved space. This should never fail on internal pages. */ if (unlikely(itupsz > BTMaxItemSize(npage))) _bt_check_third_page(wstate->index, wstate->heap, @@ -907,8 +907,8 @@ _bt_buildadd(BTWriteState *wstate, BTPageState *state, IndexTuple itup) * choosing a split point here for a benefit that is bound to be * much smaller. * - * Since the truncated tuple is probably smaller than the - * original, it cannot just be copied in place (besides, we want + * Since the truncated tuple is often smaller than the original + * tuple, it cannot just be copied in place (besides, we want * to actually save space on the leaf page). We delete the * original high key, and add our own truncated high key at the * same offset. It's okay if the truncated tuple is slightly diff --git a/src/include/access/nbtree.h b/src/include/access/nbtree.h index 473c6f2918..a1ffa98336 100644 --- a/src/include/access/nbtree.h +++ b/src/include/access/nbtree.h @@ -219,7 +219,6 @@ typedef struct BTMetaPageData #define P_FIRSTDATAKEY(opaque) (P_RIGHTMOST(opaque) ? P_HIKEY : P_FIRSTKEY) /* - * * Notes on B-Tree tuple format, and key and non-key attributes: * * INCLUDE B-Tree indexes have non-key attributes. These are extra @@ -321,7 +320,7 @@ typedef struct BTMetaPageData /* * Get/set number of attributes within B-tree index tuple. * - * Note that this does not include an implicit tiebreaker heap-TID + * Note that this does not include an implicit tiebreaker heap TID * attribute, if any. Note also that the number of key attributes must be * explicitly represented in all heapkeyspace pivot tuples. */ @@ -424,10 +423,10 @@ typedef struct BTStackData typedef BTStackData *BTStack; /* - * BTScanInsert is the btree-private state needed to find an initial position - * for an indexscan, or to insert new tuples -- an "insertion scankey" (not to - * be confused with a search scankey). It's used to descend a B-Tree using - * _bt_search. + * BTScanInsertData is the btree-private state needed to find an initial + * position for an indexscan, or to insert new tuples -- an "insertion + * scankey" (not to be confused with a search scankey). It's used to descend + * a B-Tree using _bt_search. * * heapkeyspace indicates if we expect all keys in the index to be physically * unique because heap TID is used as a tiebreaker attribute, and if index may -- 2.40.0