Movatterモバイル変換

[0]ホーム
URL:

Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly

 Sign up
Appearance settings

Commit2a9e04f

Browse files
committed
Don't truncate away non-key attributes for leftmost downlinks.
nbtsort.c does not need to truncate away non-key attributes for theminimum key of the leftmost page on a level, since this is only used tobuild a minus infinity downlink for the level's leftmost page.Truncating away non-key attributes in advance of truncating away allattributes in _bt_sortaddtup() does not affect the correctness of CREATEINDEX, but it is misleading.Author: Peter GeogheganDiscussion:https://www.postgresql.org/message-id/CAH2-WzkAS2M3ussHG-s_Av=Zo6dPjOxyu5fNRkYnxQV+YzGQ4w@mail.gmail.com
1 parent0bef1c0 commit2a9e04f

File tree

1 file changed

+14
-16
lines changed

1 file changed

+14
-16
lines changed

‎src/backend/access/nbtree/nbtsort.c

Lines changed: 14 additions & 16 deletions
Original file line numberDiff line numberDiff line change
@@ -934,7 +934,10 @@ _bt_buildadd(BTWriteState *wstate, BTPageState *state, IndexTuple itup)
934934
state->btps_next=_bt_pagestate(wstate,state->btps_level+1);
935935

936936
Assert(BTreeTupleGetNAtts(state->btps_minkey,wstate->index)==
937-
IndexRelationGetNumberOfKeyAttributes(wstate->index));
937+
IndexRelationGetNumberOfKeyAttributes(wstate->index)||
938+
P_LEFTMOST(opageop));
939+
Assert(BTreeTupleGetNAtts(state->btps_minkey,wstate->index)==0||
940+
!P_LEFTMOST(opageop));
938941
BTreeInnerTupleSetDownLink(state->btps_minkey,oblkno);
939942
_bt_buildadd(wstate,state->btps_next,state->btps_minkey);
940943
pfree(state->btps_minkey);
@@ -974,24 +977,16 @@ _bt_buildadd(BTWriteState *wstate, BTPageState *state, IndexTuple itup)
974977
* If the new item is the first for its page, stash a copy for later. Note
975978
* this will only happen for the first item on a level; on later pages,
976979
* the first item for a page is copied from the prior page in the code
977-
* above.
980+
* above. Since the minimum key for an entire level is only used as a
981+
* minus infinity downlink, and never as a high key, there is no need to
982+
* truncate away non-key attributes at this point.
978983
*/
979984
if (last_off==P_HIKEY)
980985
{
981-
BTPageOpaquenpageop;
982-
983986
Assert(state->btps_minkey==NULL);
984-
985-
npageop= (BTPageOpaque)PageGetSpecialPointer(npage);
986-
987-
/*
988-
* Truncate included attributes of the tuple that we're going to
989-
* insert into the parent page as a downlink
990-
*/
991-
if (indnkeyatts!=indnatts&&P_ISLEAF(npageop))
992-
state->btps_minkey=_bt_nonkey_truncate(wstate->index,itup);
993-
else
994-
state->btps_minkey=CopyIndexTuple(itup);
987+
state->btps_minkey=CopyIndexTuple(itup);
988+
/* _bt_sortaddtup() will perform full truncation later */
989+
BTreeTupleSetNAtts(state->btps_minkey,0);
995990
}
996991

997992
/*
@@ -1044,7 +1039,10 @@ _bt_uppershutdown(BTWriteState *wstate, BTPageState *state)
10441039
else
10451040
{
10461041
Assert(BTreeTupleGetNAtts(s->btps_minkey,wstate->index)==
1047-
IndexRelationGetNumberOfKeyAttributes(wstate->index));
1042+
IndexRelationGetNumberOfKeyAttributes(wstate->index)||
1043+
P_LEFTMOST(opaque));
1044+
Assert(BTreeTupleGetNAtts(s->btps_minkey,wstate->index)==0||
1045+
!P_LEFTMOST(opaque));
10481046
BTreeInnerTupleSetDownLink(s->btps_minkey,blkno);
10491047
_bt_buildadd(wstate,s->btps_next,s->btps_minkey);
10501048
pfree(s->btps_minkey);

0 commit comments

Comments
 (0)
[8]ページ先頭
©2009-2025 Movatter.jp