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Make 'col IS NULL' clauses be indexable conditions.
Teodor Sigaev, with some kibitzing from Tom Lane.
This commit is contained in:
Tom Lane
parent
146c83c045
commit
f02a82b6ad
@ -1,4 +1,4 @@
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<!-- $PostgreSQL: pgsql/doc/src/sgml/catalogs.sgml,v 2.149 2007/04/02 03:49:36 tgl Exp $ -->
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<!-- $PostgreSQL: pgsql/doc/src/sgml/catalogs.sgml,v 2.150 2007/04/06 22:33:41 tgl Exp $ -->
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<!--
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Documentation of the system catalogs, directed toward PostgreSQL developers
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-->
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@ -405,6 +405,13 @@
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<entry>Does the access method support null index entries?</entry>
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</row>
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<row>
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<entry><structfield>amsearchnulls</structfield></entry>
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<entry><type>bool</type></entry>
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<entry></entry>
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<entry>Does the access method support IS NULL searches?</entry>
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</row>
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<row>
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<entry><structfield>amstorage</structfield></entry>
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<entry><type>bool</type></entry>
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@ -1,4 +1,4 @@
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<!-- $PostgreSQL: pgsql/doc/src/sgml/indexam.sgml,v 2.22 2007/02/22 22:00:22 tgl Exp $ -->
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<!-- $PostgreSQL: pgsql/doc/src/sgml/indexam.sgml,v 2.23 2007/04/06 22:33:41 tgl Exp $ -->
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<chapter id="indexam">
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<title>Index Access Method Interface Definition</title>
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@ -129,7 +129,10 @@
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It is, however, OK to omit rows where the first indexed column is null.
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Thus, <structfield>amindexnulls</structfield> should be set true only if the
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index access method indexes all rows, including arbitrary combinations of
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null values.
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null values. An index access method that sets
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<structfield>amindexnulls</structfield> may also set
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<structfield>amsearchnulls</structfield>, indicating that it supports
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<literal>IS NULL</> clauses as search conditions.
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</para>
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</sect1>
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@ -1,4 +1,4 @@
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<!-- $PostgreSQL: pgsql/doc/src/sgml/indices.sgml,v 1.70 2007/02/14 20:47:15 tgl Exp $ -->
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<!-- $PostgreSQL: pgsql/doc/src/sgml/indices.sgml,v 1.71 2007/04/06 22:33:41 tgl Exp $ -->
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<chapter id="indexes">
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<title id="indexes-title">Indexes</title>
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@ -147,8 +147,8 @@ CREATE INDEX test1_id_index ON test1 (id);
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Constructs equivalent to combinations of these operators, such as
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<literal>BETWEEN</> and <literal>IN</>, can also be implemented with
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a B-tree index search. (But note that <literal>IS NULL</> is not
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equivalent to <literal>=</> and is not indexable.)
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a B-tree index search. Also, an <literal>IS NULL</> condition on
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an index column can be used with a B-tree index.
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</para>
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<para>
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@ -180,8 +180,9 @@ CREATE INDEX test1_id_index ON test1 (id);
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Hash indexes can only handle simple equality comparisons.
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The query planner will consider using a hash index whenever an
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indexed column is involved in a comparison using the
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<literal>=</literal> operator. The following command is used to
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create a hash index:
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<literal>=</literal> operator. (But hash indexes do not support
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<literal>IS NULL</> searches.)
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The following command is used to create a hash index:
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<synopsis>
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CREATE INDEX <replaceable>name</replaceable> ON <replaceable>table</replaceable> USING hash (<replaceable>column</replaceable>);
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</synopsis>
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@ -234,6 +235,8 @@ CREATE INDEX <replaceable>name</replaceable> ON <replaceable>table</replaceable>
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(See <xref linkend="functions-geometry"> for the meaning of
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these operators.)
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Also, an <literal>IS NULL</> condition on
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an index column can be used with a GiST index.
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Many other GiST operator
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classes are available in the <literal>contrib</> collection or as separate
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projects. For more information see <xref linkend="GiST">.
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@ -266,6 +269,7 @@ CREATE INDEX <replaceable>name</replaceable> ON <replaceable>table</replaceable>
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(See <xref linkend="functions-array"> for the meaning of
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these operators.)
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GIN indexes cannot use <literal>IS NULL</> as a search condition.
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Other GIN operator classes are available in the <literal>contrib</>
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<literal>tsearch2</literal> and <literal>intarray</literal> modules.
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For more information see <xref linkend="GIN">.
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@ -1,5 +1,5 @@
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<!--
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$PostgreSQL: pgsql/doc/src/sgml/ref/create_index.sgml,v 1.61 2007/04/03 22:38:35 momjian Exp $
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$PostgreSQL: pgsql/doc/src/sgml/ref/create_index.sgml,v 1.62 2007/04/06 22:33:41 tgl Exp $
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PostgreSQL documentation
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-->
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@ -434,12 +434,6 @@ Indexes:
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to remove an index.
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</para>
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<para>
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Indexes are not used for <literal>IS NULL</> clauses by default.
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The best way to use indexes in such cases is to create a partial index
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using an <literal>IS NULL</> predicate.
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</para>
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<para>
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Prior releases of <productname>PostgreSQL</productname> also had an
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R-tree index method. This method has been removed because
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@ -8,7 +8,7 @@
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*
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/backend/access/common/scankey.c,v 1.29 2007/01/05 22:19:21 momjian Exp $
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* $PostgreSQL: pgsql/src/backend/access/common/scankey.c,v 1.30 2007/04/06 22:33:41 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -20,7 +20,8 @@
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/*
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* ScanKeyEntryInitialize
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* Initializes a scan key entry given all the field values.
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* The target procedure is specified by OID.
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* The target procedure is specified by OID (but can be invalid
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* if SK_SEARCHNULL is set).
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*
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* Note: CurrentMemoryContext at call should be as long-lived as the ScanKey
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* itself, because that's what will be used for any subsidiary info attached
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@ -40,7 +41,13 @@ ScanKeyEntryInitialize(ScanKey entry,
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entry->sk_strategy = strategy;
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entry->sk_subtype = subtype;
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entry->sk_argument = argument;
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if (RegProcedureIsValid(procedure))
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fmgr_info(procedure, &entry->sk_func);
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else
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{
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Assert(flags & SK_SEARCHNULL);
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MemSet(&entry->sk_func, 0, sizeof(entry->sk_func));
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}
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}
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/*
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@ -8,7 +8,7 @@
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/backend/access/gist/gistget.c,v 1.64 2007/01/20 18:43:35 neilc Exp $
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* $PostgreSQL: pgsql/src/backend/access/gist/gistget.c,v 1.65 2007/04/06 22:33:41 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -381,16 +381,23 @@ gistindex_keytest(IndexTuple tuple,
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if (key->sk_flags & SK_ISNULL)
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{
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/*
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* is the compared-to datum NULL? on non-leaf page it's possible
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* to have nulls in childs :(
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* On non-leaf page we can't conclude that child hasn't NULL
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* values because of assumption in GiST: uinon (VAL, NULL) is VAL
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* But if on non-leaf page key IS NULL then all childs
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* has NULL.
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*/
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if (isNull || !GistPageIsLeaf(p))
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return true;
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Assert( key->sk_flags & SK_SEARCHNULL );
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if ( GistPageIsLeaf(p) && !isNull )
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return false;
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}
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else if (isNull)
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{
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return false;
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}
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else
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{
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gistdentryinit(giststate, key->sk_attno - 1, &de,
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datum, r, p, offset,
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@ -412,6 +419,7 @@ gistindex_keytest(IndexTuple tuple,
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if (!DatumGetBool(test))
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return false;
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}
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keySize--;
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key++;
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@ -8,7 +8,7 @@
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/backend/access/nbtree/nbtsearch.c,v 1.111 2007/01/09 02:14:10 tgl Exp $
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* $PostgreSQL: pgsql/src/backend/access/nbtree/nbtsearch.c,v 1.112 2007/04/06 22:33:42 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -746,8 +746,6 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
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*
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* If goback = true, we will then step back one item, while if
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* goback = false, we will start the scan on the located item.
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*
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* it's yet other place to add some code later for is(not)null ...
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*----------
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*/
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switch (strat_total)
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@ -8,7 +8,7 @@
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*
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/backend/access/nbtree/nbtutils.c,v 1.83 2007/03/30 00:12:59 tgl Exp $
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* $PostgreSQL: pgsql/src/backend/access/nbtree/nbtutils.c,v 1.84 2007/04/06 22:33:42 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -264,12 +264,27 @@ _bt_preprocess_keys(IndexScanDesc scan)
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if (numberOfKeys == 1)
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{
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/*
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* We don't use indices for 'A is null' and 'A is not null' currently
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* and 'A < = > <> NULL' will always fail - so qual is not OK if
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* comparison value is NULL. - vadim 03/21/97
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* We treat all btree operators as strict (even if they're not so
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* marked in pg_proc). This means that it is impossible for an
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* operator condition with a NULL comparison constant to succeed,
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* and we can reject it right away.
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*
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* However, we now also support "x IS NULL" clauses as search
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* conditions, so in that case keep going. The planner has not
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* filled in any particular strategy in this case, so set it to
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* BTEqualStrategyNumber --- we can treat IS NULL as an equality
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* operator for purposes of search strategy.
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*/
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if (cur->sk_flags & SK_ISNULL)
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{
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if (cur->sk_flags & SK_SEARCHNULL)
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{
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cur->sk_strategy = BTEqualStrategyNumber;
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cur->sk_subtype = InvalidOid;
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}
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else
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so->qual_ok = false;
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}
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_bt_mark_scankey_with_indoption(cur, indoption);
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memcpy(outkeys, cur, sizeof(ScanKeyData));
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so->numberOfKeys = 1;
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@ -303,19 +318,22 @@ _bt_preprocess_keys(IndexScanDesc scan)
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{
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if (i < numberOfKeys)
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{
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/* See comments above: any NULL implies cannot match qual */
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/* See comments above about NULLs and IS NULL handling. */
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/* Note: we assume SK_ISNULL is never set in a row header key */
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if (cur->sk_flags & SK_ISNULL)
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{
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if (cur->sk_flags & SK_SEARCHNULL)
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{
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cur->sk_strategy = BTEqualStrategyNumber;
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cur->sk_subtype = InvalidOid;
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}
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else
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{
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so->qual_ok = false;
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/*
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* Quit processing so we don't try to invoke comparison
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* routines on NULLs.
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*/
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return;
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}
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}
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}
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/*
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* If we are at the end of the keys for a particular attr, finish up
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@ -344,6 +362,14 @@ _bt_preprocess_keys(IndexScanDesc scan)
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if (!chk || j == (BTEqualStrategyNumber - 1))
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continue;
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/* IS NULL together with any other predicate must fail */
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if (eq->sk_flags & SK_SEARCHNULL)
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{
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so->qual_ok = false;
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return;
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}
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if (_bt_compare_scankey_args(scan, chk, eq, chk,
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&test_result))
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{
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@ -455,6 +481,23 @@ _bt_preprocess_keys(IndexScanDesc scan)
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else
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{
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/* yup, keep only the more restrictive key */
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/* if either arg is NULL, don't try to compare */
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if ((cur->sk_flags | xform[j]->sk_flags) & SK_ISNULL)
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{
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/* at least one of them must be an IS NULL clause */
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Assert(j == (BTEqualStrategyNumber - 1));
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Assert((cur->sk_flags | xform[j]->sk_flags) & SK_SEARCHNULL);
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/* if one is and one isn't, the search must fail */
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if ((cur->sk_flags ^ xform[j]->sk_flags) & SK_SEARCHNULL)
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{
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so->qual_ok = false;
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return;
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}
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/* we have duplicate IS NULL clauses, ignore the newer one */
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continue;
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}
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if (_bt_compare_scankey_args(scan, cur, cur, xform[j],
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&test_result))
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{
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@ -798,11 +841,29 @@ _bt_checkkeys(IndexScanDesc scan,
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tupdesc,
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&isNull);
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/* btree doesn't support 'A is null' clauses, yet */
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if (key->sk_flags & SK_ISNULL)
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{
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/* we shouldn't get here, really; see _bt_preprocess_keys() */
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/* Handle IS NULL tests */
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Assert(key->sk_flags & SK_SEARCHNULL);
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if (isNull)
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continue; /* tuple satisfies this qual */
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/*
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* Tuple fails this qual. If it's a required qual for the current
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* scan direction, then we can conclude no further tuples will
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* pass, either.
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*/
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if ((key->sk_flags & SK_BT_REQFWD) &&
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ScanDirectionIsForward(dir))
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*continuescan = false;
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else if ((key->sk_flags & SK_BT_REQBKWD) &&
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ScanDirectionIsBackward(dir))
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*continuescan = false;
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/*
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* In any case, this indextuple doesn't match the qual.
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*/
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return false;
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}
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@ -8,7 +8,7 @@
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*
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/backend/executor/nodeIndexscan.c,v 1.120 2007/01/05 22:19:28 momjian Exp $
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* $PostgreSQL: pgsql/src/backend/executor/nodeIndexscan.c,v 1.121 2007/04/06 22:33:42 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -599,7 +599,7 @@ ExecInitIndexScan(IndexScan *node, EState *estate, int eflags)
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* The index quals are passed to the index AM in the form of a ScanKey array.
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* This routine sets up the ScanKeys, fills in all constant fields of the
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* ScanKeys, and prepares information about the keys that have non-constant
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* comparison values. We divide index qual expressions into four types:
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* comparison values. We divide index qual expressions into five types:
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*
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* 1. Simple operator with constant comparison value ("indexkey op constant").
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* For these, we just fill in a ScanKey containing the constant value.
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@ -620,6 +620,8 @@ ExecInitIndexScan(IndexScan *node, EState *estate, int eflags)
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* (Note that we treat all array-expressions as requiring runtime evaluation,
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* even if they happen to be constants.)
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*
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* 5. NullTest ("indexkey IS NULL"). We just fill in the ScanKey properly.
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*
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* Input params are:
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*
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* planstate: executor state node we are working for
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@ -956,6 +958,38 @@ ExecIndexBuildScanKeys(PlanState *planstate, Relation index,
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opfuncid, /* reg proc to use */
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(Datum) 0); /* constant */
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}
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else if (IsA(clause, NullTest))
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{
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/* indexkey IS NULL */
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Assert(((NullTest *) clause)->nulltesttype == IS_NULL);
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/*
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* argument should be the index key Var, possibly relabeled
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*/
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leftop = ((NullTest *) clause)->arg;
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if (leftop && IsA(leftop, RelabelType))
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leftop = ((RelabelType *) leftop)->arg;
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Assert(leftop != NULL);
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if (!(IsA(leftop, Var) &&
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var_is_rel((Var *) leftop)))
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elog(ERROR, "NullTest indexqual has wrong key");
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varattno = ((Var *) leftop)->varattno;
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/*
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* initialize the scan key's fields appropriately
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*/
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ScanKeyEntryInitialize(this_scan_key,
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SK_ISNULL | SK_SEARCHNULL,
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varattno, /* attribute number to scan */
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strategy, /* op's strategy */
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subtype, /* strategy subtype */
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InvalidOid, /* no reg proc for this */
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(Datum) 0); /* constant */
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}
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else
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elog(ERROR, "unsupported indexqual type: %d",
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(int) nodeTag(clause));
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@ -9,7 +9,7 @@
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*
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*
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* IDENTIFICATION
|
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* $PostgreSQL: pgsql/src/backend/optimizer/path/indxpath.c,v 1.218 2007/03/21 22:18:12 tgl Exp $
|
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* $PostgreSQL: pgsql/src/backend/optimizer/path/indxpath.c,v 1.219 2007/04/06 22:33:42 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -1050,6 +1050,7 @@ match_clause_to_indexcol(IndexOptInfo *index,
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* Clause must be a binary opclause, or possibly a ScalarArrayOpExpr
|
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* (which is always binary, by definition). Or it could be a
|
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* RowCompareExpr, which we pass off to match_rowcompare_to_indexcol().
|
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* Or, if the index supports it, we can handle IS NULL clauses.
|
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*/
|
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if (is_opclause(clause))
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{
|
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@ -1083,6 +1084,15 @@ match_clause_to_indexcol(IndexOptInfo *index,
|
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(RowCompareExpr *) clause,
|
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outer_relids);
|
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}
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||||
else if (index->amsearchnulls && IsA(clause, NullTest))
|
||||
{
|
||||
NullTest *nt = (NullTest *) clause;
|
||||
|
||||
if (nt->nulltesttype == IS_NULL &&
|
||||
match_index_to_operand((Node *) nt->arg, indexcol, index))
|
||||
return true;
|
||||
return false;
|
||||
}
|
||||
else
|
||||
return false;
|
||||
|
||||
@ -2102,8 +2112,8 @@ expand_indexqual_conditions(IndexOptInfo *index, List *clausegroups)
|
||||
}
|
||||
|
||||
/*
|
||||
* Else it must be an opclause (usual case), ScalarArrayOp, or
|
||||
* RowCompare
|
||||
* Else it must be an opclause (usual case), ScalarArrayOp,
|
||||
* RowCompare, or NullTest
|
||||
*/
|
||||
if (is_opclause(clause))
|
||||
{
|
||||
@ -2123,6 +2133,16 @@ expand_indexqual_conditions(IndexOptInfo *index, List *clausegroups)
|
||||
index,
|
||||
indexcol));
|
||||
}
|
||||
else if (IsA(clause, NullTest))
|
||||
{
|
||||
Assert(index->amsearchnulls);
|
||||
resultquals = lappend(resultquals,
|
||||
make_restrictinfo(clause,
|
||||
true,
|
||||
false,
|
||||
false,
|
||||
NULL));
|
||||
}
|
||||
else
|
||||
elog(ERROR, "unsupported indexqual type: %d",
|
||||
(int) nodeTag(clause));
|
||||
|
||||
@ -10,7 +10,7 @@
|
||||
*
|
||||
*
|
||||
* IDENTIFICATION
|
||||
* $PostgreSQL: pgsql/src/backend/optimizer/plan/createplan.c,v 1.227 2007/02/25 17:44:01 tgl Exp $
|
||||
* $PostgreSQL: pgsql/src/backend/optimizer/plan/createplan.c,v 1.228 2007/04/06 22:33:42 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
@ -18,6 +18,7 @@
|
||||
|
||||
#include <limits.h>
|
||||
|
||||
#include "access/skey.h"
|
||||
#include "nodes/makefuncs.h"
|
||||
#include "optimizer/clauses.h"
|
||||
#include "optimizer/cost.h"
|
||||
@ -1821,6 +1822,7 @@ fix_indexqual_references(List *indexquals, IndexPath *index_path,
|
||||
Oid stratlefttype;
|
||||
Oid stratrighttype;
|
||||
bool recheck;
|
||||
bool is_null_op = false;
|
||||
|
||||
Assert(IsA(rinfo, RestrictInfo));
|
||||
|
||||
@ -1907,6 +1909,17 @@ fix_indexqual_references(List *indexquals, IndexPath *index_path,
|
||||
&opfamily);
|
||||
clause_op = saop->opno;
|
||||
}
|
||||
else if (IsA(clause, NullTest))
|
||||
{
|
||||
NullTest *nt = (NullTest *) clause;
|
||||
|
||||
Assert(nt->nulltesttype == IS_NULL);
|
||||
nt->arg = (Expr *) fix_indexqual_operand((Node *) nt->arg,
|
||||
index,
|
||||
&opfamily);
|
||||
is_null_op = true;
|
||||
clause_op = InvalidOid; /* keep compiler quiet */
|
||||
}
|
||||
else
|
||||
{
|
||||
elog(ERROR, "unsupported indexqual type: %d",
|
||||
@ -1916,9 +1929,19 @@ fix_indexqual_references(List *indexquals, IndexPath *index_path,
|
||||
|
||||
*fixed_indexquals = lappend(*fixed_indexquals, clause);
|
||||
|
||||
if (is_null_op)
|
||||
{
|
||||
/* IS NULL doesn't have a clause_op */
|
||||
stratno = InvalidStrategy;
|
||||
stratrighttype = InvalidOid;
|
||||
/* We assume it's non-lossy ... might need more work someday */
|
||||
recheck = false;
|
||||
}
|
||||
else
|
||||
{
|
||||
/*
|
||||
* Look up the (possibly commuted) operator in the operator family to
|
||||
* get its strategy number and the recheck indicator. This also
|
||||
* Look up the (possibly commuted) operator in the operator family
|
||||
* to get its strategy number and the recheck indicator. This also
|
||||
* double-checks that we found an operator matching the index.
|
||||
*/
|
||||
get_op_opfamily_properties(clause_op, opfamily,
|
||||
@ -1926,6 +1949,7 @@ fix_indexqual_references(List *indexquals, IndexPath *index_path,
|
||||
&stratlefttype,
|
||||
&stratrighttype,
|
||||
&recheck);
|
||||
}
|
||||
|
||||
*indexstrategy = lappend_int(*indexstrategy, stratno);
|
||||
*indexsubtype = lappend_oid(*indexsubtype, stratrighttype);
|
||||
|
||||
@ -9,7 +9,7 @@
|
||||
*
|
||||
*
|
||||
* IDENTIFICATION
|
||||
* $PostgreSQL: pgsql/src/backend/optimizer/util/plancat.c,v 1.132 2007/01/20 23:13:01 tgl Exp $
|
||||
* $PostgreSQL: pgsql/src/backend/optimizer/util/plancat.c,v 1.133 2007/04/06 22:33:42 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
@ -187,6 +187,7 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
|
||||
info->relam = indexRelation->rd_rel->relam;
|
||||
info->amcostestimate = indexRelation->rd_am->amcostestimate;
|
||||
info->amoptionalkey = indexRelation->rd_am->amoptionalkey;
|
||||
info->amsearchnulls = indexRelation->rd_am->amsearchnulls;
|
||||
|
||||
/*
|
||||
* Fetch the ordering operators associated with the index, if any.
|
||||
|
||||
@ -15,7 +15,7 @@
|
||||
*
|
||||
*
|
||||
* IDENTIFICATION
|
||||
* $PostgreSQL: pgsql/src/backend/utils/adt/selfuncs.c,v 1.231 2007/03/27 23:21:10 tgl Exp $
|
||||
* $PostgreSQL: pgsql/src/backend/utils/adt/selfuncs.c,v 1.232 2007/04/06 22:33:42 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
@ -4992,6 +4992,7 @@ btcostestimate(PG_FUNCTION_ARGS)
|
||||
int indexcol;
|
||||
bool eqQualHere;
|
||||
bool found_saop;
|
||||
bool found_null_op;
|
||||
double num_sa_scans;
|
||||
ListCell *l;
|
||||
|
||||
@ -5016,6 +5017,7 @@ btcostestimate(PG_FUNCTION_ARGS)
|
||||
indexcol = 0;
|
||||
eqQualHere = false;
|
||||
found_saop = false;
|
||||
found_null_op = false;
|
||||
num_sa_scans = 1;
|
||||
foreach(l, indexQuals)
|
||||
{
|
||||
@ -5025,6 +5027,7 @@ btcostestimate(PG_FUNCTION_ARGS)
|
||||
*rightop;
|
||||
Oid clause_op;
|
||||
int op_strategy;
|
||||
bool is_null_op = false;
|
||||
|
||||
Assert(IsA(rinfo, RestrictInfo));
|
||||
clause = rinfo->clause;
|
||||
@ -5051,6 +5054,17 @@ btcostestimate(PG_FUNCTION_ARGS)
|
||||
clause_op = saop->opno;
|
||||
found_saop = true;
|
||||
}
|
||||
else if (IsA(clause, NullTest))
|
||||
{
|
||||
NullTest *nt = (NullTest *) clause;
|
||||
|
||||
Assert(nt->nulltesttype == IS_NULL);
|
||||
leftop = (Node *) nt->arg;
|
||||
rightop = NULL;
|
||||
clause_op = InvalidOid;
|
||||
found_null_op = true;
|
||||
is_null_op = true;
|
||||
}
|
||||
else
|
||||
{
|
||||
elog(ERROR, "unsupported indexqual type: %d",
|
||||
@ -5088,11 +5102,20 @@ btcostestimate(PG_FUNCTION_ARGS)
|
||||
break;
|
||||
}
|
||||
}
|
||||
/* check for equality operator */
|
||||
if (is_null_op)
|
||||
{
|
||||
/* IS NULL is like = for purposes of selectivity determination */
|
||||
eqQualHere = true;
|
||||
}
|
||||
else
|
||||
{
|
||||
op_strategy = get_op_opfamily_strategy(clause_op,
|
||||
index->opfamily[indexcol]);
|
||||
Assert(op_strategy != 0); /* not a member of opfamily?? */
|
||||
if (op_strategy == BTEqualStrategyNumber)
|
||||
eqQualHere = true;
|
||||
}
|
||||
/* count up number of SA scans induced by indexBoundQuals only */
|
||||
if (IsA(clause, ScalarArrayOpExpr))
|
||||
{
|
||||
@ -5108,12 +5131,14 @@ btcostestimate(PG_FUNCTION_ARGS)
|
||||
/*
|
||||
* If index is unique and we found an '=' clause for each column, we can
|
||||
* just assume numIndexTuples = 1 and skip the expensive
|
||||
* clauselist_selectivity calculations.
|
||||
* clauselist_selectivity calculations. However, a ScalarArrayOp or
|
||||
* NullTest invalidates that theory, even though it sets eqQualHere.
|
||||
*/
|
||||
if (index->unique &&
|
||||
indexcol == index->ncolumns - 1 &&
|
||||
eqQualHere &&
|
||||
!found_saop)
|
||||
!found_saop &&
|
||||
!found_null_op)
|
||||
numIndexTuples = 1.0;
|
||||
else
|
||||
{
|
||||
|
||||
@ -7,7 +7,7 @@
|
||||
* Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* $PostgreSQL: pgsql/src/include/access/skey.h,v 1.34 2007/01/05 22:19:51 momjian Exp $
|
||||
* $PostgreSQL: pgsql/src/include/access/skey.h,v 1.35 2007/04/06 22:33:42 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
@ -52,6 +52,12 @@ typedef uint16 StrategyNumber;
|
||||
* the operator. When using a ScanKey in a heap scan, these fields are not
|
||||
* used and may be set to InvalidStrategy/InvalidOid.
|
||||
*
|
||||
* A ScanKey can also represent a condition "column IS NULL"; this is signaled
|
||||
* by the SK_SEARCHNULL flag bit. In this case the argument is always NULL,
|
||||
* and the sk_strategy, sk_subtype, and sk_func fields are not used (unless
|
||||
* set by the index AM). Currently, SK_SEARCHNULL is supported only for
|
||||
* index scans, not heap scans; and not all index AMs support it.
|
||||
*
|
||||
* Note: in some places, ScanKeys are used as a convenient representation
|
||||
* for the invocation of an access method support procedure. In this case
|
||||
* sk_strategy/sk_subtype are not meaningful, and sk_func may refer to a
|
||||
@ -111,6 +117,7 @@ typedef ScanKeyData *ScanKey;
|
||||
#define SK_ROW_HEADER 0x0004 /* row comparison header (see above) */
|
||||
#define SK_ROW_MEMBER 0x0008 /* row comparison member (see above) */
|
||||
#define SK_ROW_END 0x0010 /* last row comparison member (see above) */
|
||||
#define SK_SEARCHNULL 0x0020 /* scankey represents a "col IS NULL" qual */
|
||||
|
||||
|
||||
/*
|
||||
|
||||
@ -37,7 +37,7 @@
|
||||
* Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* $PostgreSQL: pgsql/src/include/catalog/catversion.h,v 1.400 2007/04/06 04:21:43 tgl Exp $
|
||||
* $PostgreSQL: pgsql/src/include/catalog/catversion.h,v 1.401 2007/04/06 22:33:43 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
@ -53,6 +53,6 @@
|
||||
*/
|
||||
|
||||
/* yyyymmddN */
|
||||
#define CATALOG_VERSION_NO 200704051
|
||||
#define CATALOG_VERSION_NO 200704061
|
||||
|
||||
#endif
|
||||
|
||||
@ -8,7 +8,7 @@
|
||||
* Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* $PostgreSQL: pgsql/src/include/catalog/pg_am.h,v 1.50 2007/01/20 23:13:01 tgl Exp $
|
||||
* $PostgreSQL: pgsql/src/include/catalog/pg_am.h,v 1.51 2007/04/06 22:33:43 tgl Exp $
|
||||
*
|
||||
* NOTES
|
||||
* the genbki.sh script reads this file and generates .bki
|
||||
@ -50,6 +50,7 @@ CATALOG(pg_am,2601)
|
||||
bool amcanmulticol; /* does AM support multi-column indexes? */
|
||||
bool amoptionalkey; /* can query omit key for the first column? */
|
||||
bool amindexnulls; /* does AM support NULL index entries? */
|
||||
bool amsearchnulls; /* can AM search for NULL index entries? */
|
||||
bool amstorage; /* can storage type differ from column type? */
|
||||
bool amclusterable; /* does AM support cluster command? */
|
||||
regproc aminsert; /* "insert this tuple" function */
|
||||
@ -78,7 +79,7 @@ typedef FormData_pg_am *Form_pg_am;
|
||||
* compiler constants for pg_am
|
||||
* ----------------
|
||||
*/
|
||||
#define Natts_pg_am 23
|
||||
#define Natts_pg_am 24
|
||||
#define Anum_pg_am_amname 1
|
||||
#define Anum_pg_am_amstrategies 2
|
||||
#define Anum_pg_am_amsupport 3
|
||||
@ -87,37 +88,38 @@ typedef FormData_pg_am *Form_pg_am;
|
||||
#define Anum_pg_am_amcanmulticol 6
|
||||
#define Anum_pg_am_amoptionalkey 7
|
||||
#define Anum_pg_am_amindexnulls 8
|
||||
#define Anum_pg_am_amstorage 9
|
||||
#define Anum_pg_am_amclusterable 10
|
||||
#define Anum_pg_am_aminsert 11
|
||||
#define Anum_pg_am_ambeginscan 12
|
||||
#define Anum_pg_am_amgettuple 13
|
||||
#define Anum_pg_am_amgetmulti 14
|
||||
#define Anum_pg_am_amrescan 15
|
||||
#define Anum_pg_am_amendscan 16
|
||||
#define Anum_pg_am_ammarkpos 17
|
||||
#define Anum_pg_am_amrestrpos 18
|
||||
#define Anum_pg_am_ambuild 19
|
||||
#define Anum_pg_am_ambulkdelete 20
|
||||
#define Anum_pg_am_amvacuumcleanup 21
|
||||
#define Anum_pg_am_amcostestimate 22
|
||||
#define Anum_pg_am_amoptions 23
|
||||
#define Anum_pg_am_amsearchnulls 9
|
||||
#define Anum_pg_am_amstorage 10
|
||||
#define Anum_pg_am_amclusterable 11
|
||||
#define Anum_pg_am_aminsert 12
|
||||
#define Anum_pg_am_ambeginscan 13
|
||||
#define Anum_pg_am_amgettuple 14
|
||||
#define Anum_pg_am_amgetmulti 15
|
||||
#define Anum_pg_am_amrescan 16
|
||||
#define Anum_pg_am_amendscan 17
|
||||
#define Anum_pg_am_ammarkpos 18
|
||||
#define Anum_pg_am_amrestrpos 19
|
||||
#define Anum_pg_am_ambuild 20
|
||||
#define Anum_pg_am_ambulkdelete 21
|
||||
#define Anum_pg_am_amvacuumcleanup 22
|
||||
#define Anum_pg_am_amcostestimate 23
|
||||
#define Anum_pg_am_amoptions 24
|
||||
|
||||
/* ----------------
|
||||
* initial contents of pg_am
|
||||
* ----------------
|
||||
*/
|
||||
|
||||
DATA(insert OID = 403 ( btree 5 1 t t t t t f t btinsert btbeginscan btgettuple btgetmulti btrescan btendscan btmarkpos btrestrpos btbuild btbulkdelete btvacuumcleanup btcostestimate btoptions ));
|
||||
DATA(insert OID = 403 ( btree 5 1 t t t t t t f t btinsert btbeginscan btgettuple btgetmulti btrescan btendscan btmarkpos btrestrpos btbuild btbulkdelete btvacuumcleanup btcostestimate btoptions ));
|
||||
DESCR("b-tree index access method");
|
||||
#define BTREE_AM_OID 403
|
||||
DATA(insert OID = 405 ( hash 1 1 f f f f f f f hashinsert hashbeginscan hashgettuple hashgetmulti hashrescan hashendscan hashmarkpos hashrestrpos hashbuild hashbulkdelete hashvacuumcleanup hashcostestimate hashoptions ));
|
||||
DATA(insert OID = 405 ( hash 1 1 f f f f f f f f hashinsert hashbeginscan hashgettuple hashgetmulti hashrescan hashendscan hashmarkpos hashrestrpos hashbuild hashbulkdelete hashvacuumcleanup hashcostestimate hashoptions ));
|
||||
DESCR("hash index access method");
|
||||
#define HASH_AM_OID 405
|
||||
DATA(insert OID = 783 ( gist 0 7 f f t t t t t gistinsert gistbeginscan gistgettuple gistgetmulti gistrescan gistendscan gistmarkpos gistrestrpos gistbuild gistbulkdelete gistvacuumcleanup gistcostestimate gistoptions ));
|
||||
DATA(insert OID = 783 ( gist 0 7 f f t t t t t t gistinsert gistbeginscan gistgettuple gistgetmulti gistrescan gistendscan gistmarkpos gistrestrpos gistbuild gistbulkdelete gistvacuumcleanup gistcostestimate gistoptions ));
|
||||
DESCR("GiST index access method");
|
||||
#define GIST_AM_OID 783
|
||||
DATA(insert OID = 2742 ( gin 0 4 f f f f f t f gininsert ginbeginscan gingettuple gingetmulti ginrescan ginendscan ginmarkpos ginrestrpos ginbuild ginbulkdelete ginvacuumcleanup gincostestimate ginoptions ));
|
||||
DATA(insert OID = 2742 ( gin 0 4 f f f f f f t f gininsert ginbeginscan gingettuple gingetmulti ginrescan ginendscan ginmarkpos ginrestrpos ginbuild ginbulkdelete ginvacuumcleanup gincostestimate ginoptions ));
|
||||
DESCR("GIN index access method");
|
||||
#define GIN_AM_OID 2742
|
||||
|
||||
|
||||
@ -7,7 +7,7 @@
|
||||
* Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* $PostgreSQL: pgsql/src/include/nodes/relation.h,v 1.139 2007/02/27 01:11:26 tgl Exp $
|
||||
* $PostgreSQL: pgsql/src/include/nodes/relation.h,v 1.140 2007/04/06 22:33:43 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
@ -397,6 +397,7 @@ typedef struct IndexOptInfo
|
||||
bool predOK; /* true if predicate matches query */
|
||||
bool unique; /* true if a unique index */
|
||||
bool amoptionalkey; /* can query omit key for the first column? */
|
||||
bool amsearchnulls; /* can AM search for NULL index entries? */
|
||||
} IndexOptInfo;
|
||||
|
||||
|
||||
|
||||
@ -75,6 +75,12 @@ SELECT count(*) FROM fast_emp4000 WHERE home_base && '(1000,1000,0,0)'::box;
|
||||
2
|
||||
(1 row)
|
||||
|
||||
SELECT count(*) FROM fast_emp4000 WHERE home_base IS NULL;
|
||||
count
|
||||
-------
|
||||
278
|
||||
(1 row)
|
||||
|
||||
SELECT * FROM polygon_tbl WHERE f1 ~ '((1,1),(2,2),(2,1))'::polygon
|
||||
ORDER BY (poly_center(f1))[0];
|
||||
f1
|
||||
@ -125,6 +131,12 @@ SELECT count(*) FROM fast_emp4000 WHERE home_base && '(1000,1000,0,0)'::box;
|
||||
2
|
||||
(1 row)
|
||||
|
||||
SELECT count(*) FROM fast_emp4000 WHERE home_base IS NULL;
|
||||
count
|
||||
-------
|
||||
278
|
||||
(1 row)
|
||||
|
||||
SELECT * FROM polygon_tbl WHERE f1 ~ '((1,1),(2,2),(2,1))'::polygon
|
||||
ORDER BY (poly_center(f1))[0];
|
||||
f1
|
||||
@ -410,3 +422,71 @@ Indexes:
|
||||
"std_index" btree (f2)
|
||||
|
||||
DROP TABLE concur_heap;
|
||||
--
|
||||
-- Tests for IS NULL with b-tree indexes
|
||||
--
|
||||
SELECT unique1, unique2 INTO onek_with_null FROM onek;
|
||||
INSERT INTO onek_with_null (unique1,unique2) VALUES (NULL, -1), (NULL, NULL);
|
||||
CREATE UNIQUE INDEX onek_nulltest ON onek_with_null (unique2,unique1);
|
||||
SET enable_seqscan = OFF;
|
||||
SET enable_indexscan = ON;
|
||||
SET enable_bitmapscan = ON;
|
||||
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL;
|
||||
count
|
||||
-------
|
||||
2
|
||||
(1 row)
|
||||
|
||||
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL AND unique2 IS NULL;
|
||||
count
|
||||
-------
|
||||
1
|
||||
(1 row)
|
||||
|
||||
DROP INDEX onek_nulltest;
|
||||
CREATE UNIQUE INDEX onek_nulltest ON onek_with_null (unique2 desc,unique1);
|
||||
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL;
|
||||
count
|
||||
-------
|
||||
2
|
||||
(1 row)
|
||||
|
||||
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL AND unique2 IS NULL;
|
||||
count
|
||||
-------
|
||||
1
|
||||
(1 row)
|
||||
|
||||
DROP INDEX onek_nulltest;
|
||||
CREATE UNIQUE INDEX onek_nulltest ON onek_with_null (unique2 desc nulls last,unique1);
|
||||
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL;
|
||||
count
|
||||
-------
|
||||
2
|
||||
(1 row)
|
||||
|
||||
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL AND unique2 IS NULL;
|
||||
count
|
||||
-------
|
||||
1
|
||||
(1 row)
|
||||
|
||||
DROP INDEX onek_nulltest;
|
||||
CREATE UNIQUE INDEX onek_nulltest ON onek_with_null (unique2 nulls first,unique1);
|
||||
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL;
|
||||
count
|
||||
-------
|
||||
2
|
||||
(1 row)
|
||||
|
||||
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL AND unique2 IS NULL;
|
||||
count
|
||||
-------
|
||||
1
|
||||
(1 row)
|
||||
|
||||
RESET enable_seqscan;
|
||||
RESET enable_indexscan;
|
||||
RESET enable_bitmapscan;
|
||||
|
||||
DROP TABLE onek_with_null;
|
||||
|
||||
@ -96,6 +96,8 @@ SELECT * FROM fast_emp4000
|
||||
|
||||
SELECT count(*) FROM fast_emp4000 WHERE home_base && '(1000,1000,0,0)'::box;
|
||||
|
||||
SELECT count(*) FROM fast_emp4000 WHERE home_base IS NULL;
|
||||
|
||||
SELECT * FROM polygon_tbl WHERE f1 ~ '((1,1),(2,2),(2,1))'::polygon
|
||||
ORDER BY (poly_center(f1))[0];
|
||||
|
||||
@ -119,6 +121,8 @@ SELECT * FROM fast_emp4000
|
||||
|
||||
SELECT count(*) FROM fast_emp4000 WHERE home_base && '(1000,1000,0,0)'::box;
|
||||
|
||||
SELECT count(*) FROM fast_emp4000 WHERE home_base IS NULL;
|
||||
|
||||
SELECT * FROM polygon_tbl WHERE f1 ~ '((1,1),(2,2),(2,1))'::polygon
|
||||
ORDER BY (poly_center(f1))[0];
|
||||
|
||||
@ -259,3 +263,45 @@ COMMIT;
|
||||
\d concur_heap
|
||||
|
||||
DROP TABLE concur_heap;
|
||||
|
||||
--
|
||||
-- Tests for IS NULL with b-tree indexes
|
||||
--
|
||||
|
||||
SELECT unique1, unique2 INTO onek_with_null FROM onek;
|
||||
INSERT INTO onek_with_null (unique1,unique2) VALUES (NULL, -1), (NULL, NULL);
|
||||
CREATE UNIQUE INDEX onek_nulltest ON onek_with_null (unique2,unique1);
|
||||
|
||||
SET enable_seqscan = OFF;
|
||||
SET enable_indexscan = ON;
|
||||
SET enable_bitmapscan = ON;
|
||||
|
||||
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL;
|
||||
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL AND unique2 IS NULL;
|
||||
|
||||
DROP INDEX onek_nulltest;
|
||||
|
||||
CREATE UNIQUE INDEX onek_nulltest ON onek_with_null (unique2 desc,unique1);
|
||||
|
||||
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL;
|
||||
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL AND unique2 IS NULL;
|
||||
|
||||
DROP INDEX onek_nulltest;
|
||||
|
||||
CREATE UNIQUE INDEX onek_nulltest ON onek_with_null (unique2 desc nulls last,unique1);
|
||||
|
||||
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL;
|
||||
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL AND unique2 IS NULL;
|
||||
|
||||
DROP INDEX onek_nulltest;
|
||||
|
||||
CREATE UNIQUE INDEX onek_nulltest ON onek_with_null (unique2 nulls first,unique1);
|
||||
|
||||
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL;
|
||||
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL AND unique2 IS NULL;
|
||||
|
||||
RESET enable_seqscan;
|
||||
RESET enable_indexscan;
|
||||
RESET enable_bitmapscan;
|
||||
|
||||
DROP TABLE onek_with_null;
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user