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Indexes with INCLUDE columns and their support in B-tree

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This patch introduces INCLUDE clause to index definition.  This clause
specifies a list of columns which will be included as a non-key part in
the index.  The INCLUDE columns exist solely to allow more queries to
benefit from index-only scans.  Also, such columns don't need to have
appropriate operator classes.  Expressions are not supported as INCLUDE
columns since they cannot be used in index-only scans.

Index access methods supporting INCLUDE are indicated by amcaninclude flag
in IndexAmRoutine.  For now, only B-tree indexes support INCLUDE clause.

In B-tree indexes INCLUDE columns are truncated from pivot index tuples
(tuples located in non-leaf pages and high keys).  Therefore, B-tree indexes
now might have variable number of attributes.  This patch also provides
generic facility to support that: pivot tuples contain number of their
attributes in t_tid.ip_posid.  Free 13th bit of t_info is used for indicating
that.  This facility will simplify further support of index suffix truncation.
The changes of above are backward-compatible, pg_upgrade doesn't need special
handling of B-tree indexes for that.

Bump catalog version

Author: Anastasia Lubennikova with contribition by Alexander Korotkov and me
Reviewed by: Peter Geoghegan, Tomas Vondra, Antonin Houska, Jeff Janes,
			 David Rowley, Alexander Korotkov
Discussion: https://www.postgresql.org/message-id/flat/56168952.4010101@postgrespro.ru
This commit is contained in:
Teodor Sigaev
2018-04-07 23:00:39 +03:00
parent 01bb85169a
commit 8224de4f42
89 changed files with 2112 additions and 467 deletions
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19
src/backend/access/index/genam.c
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@@ -158,7 +158,8 @@ IndexScanEnd(IndexScanDesc scan)
*
* Construct a string describing the contents of an index entry, in the
* form "(key_name, ...)=(key_value, ...)". This is currently used
* for building unique-constraint and exclusion-constraint error messages.
* for building unique-constraint and exclusion-constraint error messages,
* so only key columns of the index are checked and printed.
*
* Note that if the user does not have permissions to view all of the
* columns involved then a NULL is returned. Returning a partial key seems
@@ -180,13 +181,15 @@ BuildIndexValueDescription(Relation indexRelation,
StringInfoData buf;
Form_pg_index idxrec;
HeapTuple ht_idx;
int natts = indexRelation->rd_rel->relnatts;
int indnkeyatts;
int i;
int keyno;
Oid indexrelid = RelationGetRelid(indexRelation);
Oid indrelid;
AclResult aclresult;
indnkeyatts = IndexRelationGetNumberOfKeyAttributes(indexRelation);
/*
* Check permissions- if the user does not have access to view all of the
* key columns then return NULL to avoid leaking data.
@@ -224,7 +227,7 @@ BuildIndexValueDescription(Relation indexRelation,
* No table-level access, so step through the columns in the index and
* make sure the user has SELECT rights on all of them.
*/
for (keyno = 0; keyno < idxrec->indnatts; keyno++)
for (keyno = 0; keyno < idxrec->indnkeyatts; keyno++)
{
AttrNumber attnum = idxrec->indkey.values[keyno];
@@ -250,7 +253,7 @@ BuildIndexValueDescription(Relation indexRelation,
appendStringInfo(&buf, "(%s)=(",
pg_get_indexdef_columns(indexrelid, true));
for (i = 0; i < natts; i++)
for (i = 0; i < indnkeyatts; i++)
{
char *val;
@@ -368,7 +371,7 @@ systable_beginscan(Relation heapRelation,
{
int j;
for (j = 0; j < irel->rd_index->indnatts; j++)
for (j = 0; j < IndexRelationGetNumberOfAttributes(irel); j++)
{
if (key[i].sk_attno == irel->rd_index->indkey.values[j])
{
@@ -376,7 +379,7 @@ systable_beginscan(Relation heapRelation,
break;
}
}
if (j == irel->rd_index->indnatts)
if (j == IndexRelationGetNumberOfAttributes(irel))
elog(ERROR, "column is not in index");
}
@@ -570,7 +573,7 @@ systable_beginscan_ordered(Relation heapRelation,
{
int j;
for (j = 0; j < indexRelation->rd_index->indnatts; j++)
for (j = 0; j < IndexRelationGetNumberOfAttributes(indexRelation); j++)
{
if (key[i].sk_attno == indexRelation->rd_index->indkey.values[j])
{
@@ -578,7 +581,7 @@ systable_beginscan_ordered(Relation heapRelation,
break;
}
}
if (j == indexRelation->rd_index->indnatts)
if (j == IndexRelationGetNumberOfAttributes(indexRelation))
elog(ERROR, "column is not in index");
}