php-doc-en/reference/mongo/mongocursor/addoption.xml

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<refentry xml:id="mongocursor.addoption" xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink">
 <refnamediv>
  <refname>MongoCursor::addOption</refname>
  <refpurpose>Adds a top-level key/value pair to a query</refpurpose>
 </refnamediv>

 <refsect1 role="description">
  &reftitle.description;
  <methodsynopsis>
   <modifier>public</modifier> <type>MongoCursor</type><methodname>MongoCursor::addOption</methodname>
   <methodparam><type>string</type><parameter>key</parameter></methodparam>
   <methodparam><type>mixed</type><parameter>value</parameter></methodparam>
  </methodsynopsis>
  <para>
   This is an advanced function and should not be used unless you know what 
   you're doing.
  </para>
  <para>
   A query can optionally be nested in a "query" field if other options, such as
   a sort or hint, are given.  For instance, adding a sort causes the query 
   to become a subfield of a bigger query object, like:
   <programlisting role="php">
<![CDATA[
<?php

$query = array("query" => $query, "orderby" => $sort);

?>
]]>
   </programlisting>
  </para>
  <para>
   This method is for adding a top-level field to a query.  It makes the query a
   subobject (if it isn't already) and adds the key/value pair of your chosing
   to the top level.
  </para>
  <warning>
   <para>
    It cannot be used to add extra criteria to a query on the fly.  For instance,
    this <emphasis>will not</emphasis> work:
    <programlisting role="php">
<![CDATA[
<?php

// NOT CORRECT
$cursor = $users->find()->addOption("name", "joe")->addOption("age", 20);

?>
]]>
    </programlisting>
    This <emphasis>does not</emphasis> query for a user named "joe" with an age of 20.
   </para>
  </warning>
 </refsect1>

 <refsect1 role="parameters">
  &reftitle.parameters;
  <para>
   <variablelist>
    <varlistentry>
     <term>
      <parameter>key</parameter>
     </term>
     <listitem>
      <para>
       Fieldname to add.
      </para>
     </listitem>
    </varlistentry>   
    <varlistentry>
     <term>
      <parameter>value</parameter>
     </term>
     <listitem>
      <para>
       Value to add.
      </para>
     </listitem>
    </varlistentry>   
   </variablelist>
  </para>
 </refsect1>

 <refsect1 role="returnvalues">
  &reftitle.returnvalues;  
  <para>
   Returns this cursor.
  </para>
 </refsect1>

 <refsect1 role="errors">
  &reftitle.errors;
  <para>
   Throws <classname>MongoCursorException</classname> if this cursor has started iterating.
  </para>
 </refsect1>

 <refsect1 role="examples">
  &reftitle.examples;
  <example>
   <title>Adding a comment with <function>MongoCursor::addOption</function> example</title>
   <para>
    MongoDB supports special options to be send to the server. The shell uses
    the <literal>_addSpecial</literal> option to send a
    <literal>$comment</literal> to the server. This comment will show up in
    the profiling log (for slow queries f.e.). In the PHP driver, you use the
    <function>MongoCursor::addOption</function> method.
   </para>
   <programlisting role="php">
<![CDATA[
<?php
$m = new MongoClient;
$c = $m->demo->demo;
$cursor = $c->find();
$cursor->addOption('$comment', "This comment will show up in the profiling log");

foreach ($cursor as $document) { /* empty */ }
?>
]]>
   </programlisting>
   &example.outputs.similar;
   <screen>
<![CDATA[
{
    "op" : "query",
    "ns" : "demo.demo",
    "query" : {
        "$query" : {
             
        },
        "$comment" : "This comment will show up in the profiling log"
    },
    "cursorid" : 168463566447,
    "ntoreturn" : 0,
    "ntoskip" : 0,
    "nscanned" : 101,
    "nscannedObjects" : 101,
    "keyUpdates" : 0,
    "numYield" : 0,
…
]]>
   </screen>
  </example>

  <example>
   <title><function>MongoCursor::addOption</function> example</title>
   <para>
    Using <function>MongoCursor::skip</function> to skip over millions of 
    results can become slow.  One way around this is to use 
    <literal>$min</literal> or <literal>$max</literal> options for the query.
    These can be handy, but they require an index on exactly the fields being 
    searched for.  This is an example of how to use <literal>$min</literal> as
    an alternative to <function>MongoCursor::skip</function>.
   </para>
   <programlisting role="php">
<![CDATA[
<?php

// make sure we have an index
$c->ensureIndex(array("ts" => 1));

// you may have to modify this to run in a reasonable amount of time on slow 
// machines (should take about 30 seconds on a good machine)
for ($i = 0; $i < 30000000; $i++) {
    $c->insert(array("ts" => new MongoDate(), "i" => $i));
}

$now = strtotime("now");

// find documents inserted in the last 2 seconds
$cursor = $c->find()->addOption('$min', array("ts" => $now-2));

?>
]]>
   </programlisting>
  </example>
 </refsect1>
</refentry>
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