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Start updating for the v7.0 release.

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Use "generic functions" for math and other routines.
Use SQL92 "type 'literal'" syntax rather than Postgres "'literal'::type".
This commit is contained in:
Thomas G. Lockhart
2000-03-27 17:14:43 +00:00
parent 2dabd2cd1f
commit 39f69bc38f
34 changed files with 1781 additions and 1815 deletions
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30
doc/src/sgml/ref/create_operator.sgml
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@@ -1,5 +1,5 @@
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/ref/create_operator.sgml,v 1.12 2000/03/18 18:03:12 tgl Exp $
$Header: /cvsroot/pgsql/doc/src/sgml/ref/create_operator.sgml,v 1.13 2000/03/27 17:14:42 thomas Exp $
Postgres documentation
-->
@@ -20,7 +20,7 @@ Postgres documentation
</refnamediv>
<refsynopsisdiv>
<refsynopsisdivinfo>
<date>1999-07-20</date>
<date>2000-03-25</date>
</refsynopsisdivinfo>
<synopsis>
CREATE OPERATOR <replaceable>name</replaceable> ( PROCEDURE = <replaceable class="parameter">func_name</replaceable>
@@ -32,7 +32,7 @@ CREATE OPERATOR <replaceable>name</replaceable> ( PROCEDURE = <replaceable class
<refsect2 id="R2-SQL-CREATEOPERATOR-1">
<refsect2info>
<date>1999-04-14</date>
<date>2000-03-25</date>
</refsect2info>
<title>
Inputs
@@ -138,7 +138,7 @@ CREATE OPERATOR <replaceable>name</replaceable> ( PROCEDURE = <replaceable class
<refsect2 id="R2-SQL-CREATEOPERATOR-2">
<refsect2info>
<date>1999-04-14</date>
<date>2000-03-25</date>
</refsect2info>
<title>
Outputs
@@ -162,7 +162,7 @@ CREATE
<refsect1 id="R1-SQL-CREATEOPERATOR-1">
<refsect1info>
<date>1999-04-14</date>
<date>2000-03-25</date>
</refsect1info>
<title>
Description
@@ -248,13 +248,13 @@ CREATE
Hence, the query optimizer could freely convert:
<programlisting>
"0,0,1,1"::box &gt;&gt;&gt; MYBOXES.description
box '((0,0),(1,1))' &gt;&gt;&gt; MYBOXES.description
</programlisting>
to
<programlisting>
MYBOXES.description &lt;&lt;&lt; "0,0,1,1"::box
MYBOXES.description &lt;&lt;&lt; box '((0,0),(1,1))'
</programlisting>
</para>
<para>
@@ -269,11 +269,11 @@ MYBOXES.description &lt;&lt;&lt; "0,0,1,1"::box
equal, !==.
The negator link allows the query optimizer to simplify
<programlisting>
NOT MYBOXES.description === "0,0,1,1"::box
NOT MYBOXES.description === box '((0,0),(1,1))'
</programlisting>
to
<programlisting>
MYBOXES.description !== "0,0,1,1"::box
MYBOXES.description !== box '((0,0),(1,1))'
</programlisting>
</para>
<para>
@@ -331,7 +331,7 @@ MYBOXES.description !== "0,0,1,1"::box
The RESTRICT and JOIN options assist the query optimizer in estimating
result sizes. If a clause of the form:
<programlisting>
MYBOXES.description &lt;&lt;&lt; "0,0,1,1"::box
MYBOXES.description &lt;&lt;&lt; box '((0,0),(1,1))'
</programlisting>
is present in the qualification,
then <productname>Postgres</productname> may have to
@@ -342,7 +342,7 @@ MYBOXES.description &lt;&lt;&lt; "0,0,1,1"::box
<command>CREATE FUNCTION</command>) which accepts arguments of the correct
data types and returns a floating point number. The
query optimizer simply calls this function, passing the
parameter "0,0,1,1" and multiplies the result by the relation
parameter <literal>((0,0),(1,1))</literal> and multiplies the result by the relation
size to get the expected number of instances.
</para>
<para>
@@ -356,11 +356,11 @@ MYBOXES.description &lt;&lt;&lt; "0,0,1,1"::box
<para>
The difference between the function
<programlisting>
my_procedure_1 (MYBOXES.description, "0,0,1,1"::box)
my_procedure_1 (MYBOXES.description, box '((0,0),(1,1))')
</programlisting>
and the operator
<programlisting>
MYBOXES.description === "0,0,1,1"::box
MYBOXES.description === box '((0,0),(1,1))'
</programlisting>
is that <productname>Postgres</productname>
attempts to optimize operators and can
@@ -373,7 +373,7 @@ MYBOXES.description === "0,0,1,1"::box
<refsect2 id="R2-SQL-CREATEOPERATOR-3">
<refsect2info>
<date>1999-04-14</date>
<date>2000-03-25</date>
</refsect2info>
<title>
Notes
@@ -418,7 +418,7 @@ CREATE OPERATOR === (
<refsect2 id="R2-SQL-CREATEOPERATOR-4">
<refsect2info>
<date>1999-04-14</date>
<date>2000-03-25</date>
</refsect2info>
<title>
SQL92