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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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14
src/backend/executor/execIndexing.c
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@ -648,7 +648,7 @@ check_exclusion_or_unique_constraint(Relation heap, Relation index,
Oid *constr_procs;
uint16 *constr_strats;
Oid *index_collations = index->rd_indcollation;
int index_natts = index->rd_index->indnatts;
int indnkeyatts = IndexRelationGetNumberOfKeyAttributes(index);
IndexScanDesc index_scan;
HeapTuple tup;
ScanKeyData scankeys[INDEX_MAX_KEYS];
@ -675,7 +675,7 @@ check_exclusion_or_unique_constraint(Relation heap, Relation index,
* If any of the input values are NULL, the constraint check is assumed to
* pass (i.e., we assume the operators are strict).
*/
for (i = 0; i < index_natts; i++)
for (i = 0; i < indnkeyatts; i++)
{
if (isnull[i])
return true;
@ -687,7 +687,7 @@ check_exclusion_or_unique_constraint(Relation heap, Relation index,
*/
InitDirtySnapshot(DirtySnapshot);
for (i = 0; i < index_natts; i++)
for (i = 0; i < indnkeyatts; i++)
{
ScanKeyEntryInitialize(&scankeys[i],
0,
@ -719,8 +719,8 @@ check_exclusion_or_unique_constraint(Relation heap, Relation index,
retry:
conflict = false;
found_self = false;
index_scan = index_beginscan(heap, index, &DirtySnapshot, index_natts, 0);
index_rescan(index_scan, scankeys, index_natts, NULL, 0);
index_scan = index_beginscan(heap, index, &DirtySnapshot, indnkeyatts, 0);
index_rescan(index_scan, scankeys, indnkeyatts, NULL, 0);
while ((tup = index_getnext(index_scan,
ForwardScanDirection)) != NULL)
@ -881,10 +881,10 @@ index_recheck_constraint(Relation index, Oid *constr_procs,
Datum *existing_values, bool *existing_isnull,
Datum *new_values)
{
int index_natts = index->rd_index->indnatts;
int indnkeyatts = IndexRelationGetNumberOfKeyAttributes(index);
int i;
for (i = 0; i < index_natts; i++)
for (i = 0; i < indnkeyatts; i++)
{
/* Assume the exclusion operators are strict */
if (existing_isnull[i])