Document new function oci_set_prefetch_lob()

This commit is contained in:
Christopher Jones 2021-12-11 23:18:09 +11:00
parent d83aa96e67
commit a48db6e7cd
3 changed files with 164 additions and 1 deletions

View file

@ -0,0 +1,157 @@
<?xml version="1.0" encoding="utf-8"?>
<!-- $Revision$ -->
<refentry xmlns="http://docbook.org/ns/docbook" xml:id="function.oci-set-prefetch-lob">
<refnamediv>
<refname>oci_set_prefetch_lob</refname>
<refpurpose>Sets the amount of data prefetched for each CLOB or BLOB.</refpurpose>
</refnamediv>
<refsect1 role="description">
&reftitle.description;
<methodsynopsis>
<type>bool</type><methodname>oci_set_prefetch_lob</methodname>
<methodparam><type>resource</type><parameter>statement</parameter></methodparam>
<methodparam><type>int</type><parameter>prefetch_lob_size</parameter></methodparam>
</methodsynopsis>
<para>
Sets the internal buffer size used to fetch each CLOB or BLOB value when the
implementation gets the internal Oracle LOB locator from the database after
a successful query call to <function>oci_execute</function> and for each
subsequent internal fetch request to the database. Increasing this value
can improve the performance of fetching smaller LOBs by reducing round-trips
between PHP and the database. Memory usage will change.
</para>
<para>
The value affects LOBs returned as OCI-Lob instances and also those returned
using <constant>OCI_RETURN_LOBS</constant>.
</para>
<para>
Call <function>oci_set_prefetch_lob</function> before
calling <function>oci_execute</function>. If it is not called, the value
of <link linkend="ini.oci8.prefetch-lob-size">oci8.prefetch_lob_size</link>
is used.
</para>
<para>
The LOB prefetch value should only be set with Oracle Database 12.2 or later.
</para>
</refsect1>
<refsect1 role="parameters">
&reftitle.parameters;
<para>
<variablelist>
<varlistentry>
<term><parameter>statement</parameter></term>
<listitem>
&oci.arg.statement.id;
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>prefetch_lob_size</parameter></term>
<listitem>
<para>
The number of bytes of each LOB to be prefetched, &gt;= 0
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect1>
<refsect1 role="returnvalues">
&reftitle.returnvalues;
<para>
&return.success;
</para>
</refsect1>
<refsect1 role="changelog">
&reftitle.changelog;
<para>
<informaltable>
<tgroup cols="2">
<thead>
<row>
<entry>&Version;</entry>
<entry>&Description;</entry>
</row>
</thead>
<tbody>
<row>
<entry>PECL OCI8 3.2</entry>
</row>
</tbody>
</tgroup>
</informaltable>
</para>
</refsect1>
<refsect1 role="examples">
&reftitle.examples;
<para>
<example>
<title>Changing the LOB prefetch value for a query</title>
<programlisting role="php">
<![CDATA[
<?php
$conn = oci_connect('hr', 'welcome', 'localhost/XE');
$stid = oci_parse($conn, 'SELECT myclob FROM mytable');
oci_set_prefetch_lob($stid, 100000); // Set before calling oci_execute()
oci_execute($stid);
echo "<table border='1'>\n";
while ($row = oci_fetch_array($stid, OCI_ASSOC+OCI_RETURN_NULLS+OCI_RETURN_LOBS)) {
echo "<tr>\n";
foreach ($row as $item) {
echo " <td>".($item !== null ? htmlentities($item, ENT_QUOTES) : "&nbsp;")."</td>\n";
}
echo "</tr>\n";
}
echo "</table>\n";
oci_free_statement($stid);
oci_close($conn);
?>
]]>
</programlisting>
</example>
</para>
</refsect1>
<refsect1 role="seealso">
&reftitle.seealso;
<para>
<simplelist>
<member>
<link linkend="ini.oci8.prefetch-lob-size">oci8.prefetch_lob_size</link>
ini option
</member>
</simplelist>
</para>
</refsect1>
</refentry>
<!-- Keep this comment at the end of the file
Local variables:
mode: sgml
sgml-omittag:t
sgml-shorttag:t
sgml-minimize-attributes:nil
sgml-always-quote-attributes:t
sgml-indent-step:1
sgml-indent-data:t
indent-tabs-mode:nil
sgml-parent-document:nil
sgml-default-dtd-file:"~/.phpdoc/manual.ced"
sgml-exposed-tags:nil
sgml-local-catalogs:nil
sgml-local-ecat-files:nil
End:
vim600: syn=xml fen fdm=syntax fdl=2 si
vim: et tw=78 syn=sgml
vi: ts=1 sw=1
-->

View file

@ -61,7 +61,7 @@
<row>
<entry><link linkend="ini.oci8.prefetch-lob-size">oci8.prefetch_lob_size</link></entry>
<entry>"0"</entry>
<entry>PHP_INI_ALL</entry>
<entry>PHP_INI_SYSTEM</entry>
<entry>Available since PECL OCI8 3.2.</entry>
</row>
<row>
@ -307,6 +307,11 @@
The value affects LOBs returned as OCI-Lob instances and also those
returned using <constant>OCI_RETURN_LOBS</constant>.
</para>
<para>
The value can be set per-statement
with <function>oci_set_prefetch_lob</function> prior to statement
execution.
</para>
<note>
<simpara>
Use with Oracle Database 12.2 or later.

View file

@ -89,6 +89,7 @@
<function name="oci_set_edition" from="PHP 5 &gt;= 5.3.2, PHP 7, PHP 8, PECL OCI8 &gt;= 1.4.0"/>
<function name="oci_set_module_name" from="PHP 5 &gt;= 5.3.2, PHP 7, PHP 8, PECL OCI8 &gt;= 1.4.0"/>
<function name="oci_set_prefetch" from="PHP 5, PHP 7, PHP 8, PECL OCI8 &gt;= 1.1.0"/>
<function name="oci_set_prefetch_lob" from="PHP 8.2, PECL OCI8 &gt;= 3.2"/>
<function name="oci_statement_type" from="PHP 5, PHP 7, PHP 8, PECL OCI8 &gt;= 1.1.0"/>
<function name="oci_unregister_taf_callback" from="PHP 7.0 &gt;= 7.0.23, PHP 8, PHP 7 &gt;= 7.1.9, PHP 8, PECL OCI8 &gt;= 2.1.7"/>
<function name="oci_register_taf_callback" from="PHP 7.0 &gt;= 7.0.21, PHP 8, PHP 7 &gt;= 7.1.7, PHP 8, PECL OCI8 &gt;= 2.1.7"/>