sigmasternchen/php-doc-en
1
0
Fork 0
mirror of https://github.com/sigmasternchen/php-doc-en synced 2025-03-16 00:48:54 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

ensureIndex takes options param

Browse source 
git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@291235 c90b9560-bf6c-de11-be94-00142212c4b1
This commit is contained in:
Kristina Chodorow 2009-11-23 21:45:43 +00:00
parent 7f44d50501
commit 7846ce8d16
1 changed files with 83 additions and 12 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

95
reference/mongo/mongocollection/ensureindex.xml
View file

@ -14,8 +14,8 @@
&reftitle.description;
<methodsynopsis>
<modifier>public</modifier> <type>boolean</type><methodname>MongoCollection::ensureIndex</methodname>
<methodparam><type>string|array</type><parameter>keys</parameter></methodparam>
<methodparam><type>boolean</type><parameter>unique</parameter></methodparam>
<methodparam><type>array</type><parameter>keys</parameter></methodparam>
<methodparam><type>array</type><parameter>options</parameter></methodparam>
</methodsynopsis>
<para>
A unique index cannot be created on a field if multiple existing documents do not contain the field. The field is effectively &null; for these documents and thus already non-unique.
@ -38,11 +38,32 @@
</varlistentry>
<varlistentry>
<term>
<parameter>unique</parameter>
<parameter>options</parameter>
</term>
<listitem>
<para>
If the index should be unique.
This parameter is an associative array of the form
<literal>array("optionname" => &lt;boolean&gt;, ...)</literal>. Currently
supported options are:
<itemizedlist>
<listitem>
<para>
<literal>"unique"</literal>
</para>
<para>
Create a unique index.
</para>
</listitem>
<listitem>
<para>
<literal>"dropDups"</literal>
</para>
<para>
If a unique index is being created and duplicate values exist, drop
all but one duplicate value.
</para>
</listitem>
</itemizedlist>
</para>
</listitem>
</varlistentry>
@ -57,6 +78,32 @@
</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>1.0.2</entry>
<entry>
Changed "options" parameter from boolean to array. Pre-1.0.2, the
second parameter was an optional boolean value specifying a unique
index.
</entry>
</row>
</tbody>
</tgroup>
</informaltable>
</para>
</refsect1>
<refsect1 role="examples">
&reftitle.examples;
<example>
@ -68,19 +115,43 @@
$c = new MongoCollection($db, 'foo');
// create an index on 'x' ascending
$c->ensureIndex('x');
// create an index on 'y' ascending
$c->ensureIndex(array('y' => 1));
// create an index on 'w' descending
$c->ensureIndex(array('w' => -1));
$c->ensureIndex(array('x' => 1));
// create an index on 'z' ascending and 'zz' descending
$c->ensureIndex(array('z' => 1, 'zz' => -1));
// create a unique index on 'x'
$c->ensureIndex(array('x' => 1), true);
$c->ensureIndex(array('x' => 1), array("unique" => true));
?>
]]>
</programlisting>
</example>
<example>
<title>Drop duplicates example</title>
<programlisting role="php">
<![CDATA[
<?php
$collection->insert(array("username" => "joeschmoe"));
$collection->insert(array("username" => "joeschmoe"));
/*
* index creation fails, you can't create a unique index on a key with
* non-unique values
*/
$collection->ensureIndex(array("username" => 1), array("unique" => 1));
/*
* index creation succeeds: one of the documents is removed from the collection
*/
$collection->ensureIndex(array("username" => 1), array("unique" => 1, "dropDups" => 1));
/*
* now we have a unique index, more inserts with the same username (such as the
* one below) will fail
*/
$collection->insert(array("username" => "joeschmoe"));
?>
]]>