<add>2.1</add>
<field>
<name>id</name>
+ <title>Group Contact Cache ID</title>
<type>int unsigned</type>
<required>true</required>
<comment>primary key</comment>
</primaryKey>
<field>
<name>group_id</name>
+ <title>Group</title>
<type>int unsigned</type>
<required>true</required>
<comment>FK to civicrm_group</comment>
</foreignKey>
<field>
<name>contact_id</name>
+ <title>Contact ID</title>
<type>int unsigned</type>
<required>true</required>
<comment>FK to civicrm_contact</comment>