crop-monitor/core/components/usersonline/model/schema/usersonline.mysql.schema.xml

<?xml version="1.0" encoding="UTF-8"?>
<model package="usersonline" baseClass="xPDOObject" platform="mysql" defaultEngine="MyISAM" phpdoc-package="usersonline"
	   version="1.1">

	<object class="userOnline" table="users_online" extends="xPDOSimpleObject">
		<field key="user_id" dbtype="int" precision="10" phptype="integer" null="false" default="0"/>
		<field key="lastvisit" dbtype="int" precision="20" phptype="timestamp" null="false" default="0" />
        <field key="context_key" dbtype="varchar" precision="100" phptype="string" null="false" default="web" index="index" />

        <index alias="context_key" name="context_key" primary="false" unique="false" type="BTREE">
            <column key="context_key" length="" collation="A" null="false" />
        </index>
	</object>

</model>