diff options
| -rw-r--r-- | src/backend/access/nbtree/nbtsort.c | 35 |
1 files changed, 18 insertions, 17 deletions
diff --git a/src/backend/access/nbtree/nbtsort.c b/src/backend/access/nbtree/nbtsort.c index c03998834d4..e6b72111363 100644 --- a/src/backend/access/nbtree/nbtsort.c +++ b/src/backend/access/nbtree/nbtsort.c @@ -267,7 +267,7 @@ static void _bt_build_callback(Relation index, ItemPointer tid, Datum *values, bool *isnull, bool tupleIsAlive, void *state); static Page _bt_blnewpage(uint32 level); static BTPageState *_bt_pagestate(BTWriteState *wstate, uint32 level); -static void _bt_slideleft(Page page); +static void _bt_slideleft(Page rightmostpage); static void _bt_sortaddtup(Page page, Size itemsize, IndexTuple itup, OffsetNumber itup_off, bool newfirstdataitem); @@ -721,31 +721,32 @@ _bt_pagestate(BTWriteState *wstate, uint32 level) } /* - * slide an array of ItemIds back one slot (from P_FIRSTKEY to - * P_HIKEY, overwriting P_HIKEY). we need to do this when we discover - * that we have built an ItemId array in what has turned out to be a - * P_RIGHTMOST page. + * Slide the array of ItemIds from the page back one slot (from P_FIRSTKEY to + * P_HIKEY, overwriting P_HIKEY). + * + * _bt_blnewpage() makes the P_HIKEY line pointer appear allocated, but the + * rightmost page on its level is not supposed to get a high key. Now that + * it's clear that this page is a rightmost page, remove the unneeded empty + * P_HIKEY line pointer space. */ static void -_bt_slideleft(Page page) +_bt_slideleft(Page rightmostpage) { OffsetNumber off; OffsetNumber maxoff; ItemId previi; - ItemId thisii; - if (!PageIsEmpty(page)) + maxoff = PageGetMaxOffsetNumber(rightmostpage); + Assert(maxoff >= P_FIRSTKEY); + previi = PageGetItemId(rightmostpage, P_HIKEY); + for (off = P_FIRSTKEY; off <= maxoff; off = OffsetNumberNext(off)) { - maxoff = PageGetMaxOffsetNumber(page); - previi = PageGetItemId(page, P_HIKEY); - for (off = P_FIRSTKEY; off <= maxoff; off = OffsetNumberNext(off)) - { - thisii = PageGetItemId(page, off); - *previi = *thisii; - previi = thisii; - } - ((PageHeader) page)->pd_lower -= sizeof(ItemIdData); + ItemId thisii = PageGetItemId(rightmostpage, off); + + *previi = *thisii; + previi = thisii; } + ((PageHeader) rightmostpage)->pd_lower -= sizeof(ItemIdData); } /* |