8000 Add ALTER OPERATOR command, for changing selectivity estimator functi… · postgres/postgres@321eed5 · GitHub
[go: up one dir, main page]
Skip to content

Commit 321eed5

Browse files
hlinnakahlinnaka
committed
Add ALTER OPERATOR command, for changing selectivity estimator functions.
Other options cannot be changed, as it's not totally clear if cached plans would need to be invalidated if one of the other options change. Selectivity estimator functions only change plan costs, not correctness of plans, so those should be safe. Original patch by Uriy Zhuravlev, heavily edited by me.
1 parent 705d397 commit 321eed5

File tree

13 files changed

+499
-65
lines changed

13 files changed

+499
-65
lines changed

‎doc/src/sgml/ref/alter_operator.sgml

Lines changed: 32 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -26,6 +26,11 @@ ALTER OPERATOR <replaceable>name</replaceable> ( { <replaceable>left_type</repla
2626

2727
ALTER OPERATOR <replaceable>name</replaceable> ( { <replaceable>left_type</replaceable> | NONE } , { <replaceable>right_type</replaceable> | NONE } )
2828
SET SCHEMA <replaceable>new_schema</replaceable>
29+
30+
ALTER OPERATOR <replaceable>name</replaceable> ( { <replaceable>left_type</replaceable> | NONE } , { <replaceable>right_type</replaceable> | NONE } )
31+
SET ( { RESTRICT = { <replaceable class="parameter">res_proc</replaceable> | NONE }
32+
| JOIN = { <replaceable class="parameter">join_proc</replaceable> | NONE }
33+
} [, ... ] )
2934
</synopsis>
3035
</refsynopsisdiv>
3136

@@ -34,8 +39,7 @@ ALTER OPERATOR <replaceable>name</replaceable> ( { <replaceable>left_type</repla
3439

3540
<para>
3641
<command>ALTER OPERATOR</command> changes the definition of
37-
an operator. The only currently available functionality is to change the
38-
owner of the operator.
42+
an operator.
3943
</para>
4044

4145
<para>
@@ -98,6 +102,25 @@ ALTER OPERATOR <replaceable>name</replaceable> ( { <replaceable>left_type</repla
98102
</para>
99103
</listitem>
100104
</varlistentry>
105+
106+
<varlistentry>
107+
<term><replaceable class="parameter">res_proc</replaceable></term>
108+
<listitem>
109+
<para>
110+
The restriction selectivity estimator function for this operator; write NONE to remove existing selectivity estimator.
111+
</para>
112+
</listitem>
113+
</varlistentry>
114+
115+
<varlistentry>
116+
<term><replaceable class="parameter">join_proc</replaceable></term>
117+
<listitem>
118+
<para>
119+
The join selectivity estimator function for this operator; write NONE to remove existing selectivity estimator.
120+
</para>
121+
</listitem>
122+
</varlistentry>
123+
101124
</variablelist>
102125
</refsect1>
103126

@@ -109,6 +132,13 @@ ALTER OPERATOR <replaceable>name</replaceable> ( { <replaceable>left_type</repla
109132
<programlisting>
110133
ALTER OPERATOR @@ (text, text) OWNER TO joe;
111134
</programlisting></para>
135+
136+
<para>
137+
Change the restriction and join selectivity estimator functions of a custom operator <literal>a && b</literal> for type <type>int[]</type>:
138+
<programlisting>
139+
ALTER OPERATOR && (_int4, _int4) SET (RESTRICT = _int_contsel, JOIN = _int_contjoinsel);
140+
</programlisting></para>
141+
112142
</refsect1>
113143

114144
<refsect1>

0 commit comments

Comments
 (0)
0