+ <name>parent_id</name>
+ <title>Contact Type Parent</title>
+ <type>int unsigned</type>
+ <comment>Optional FK to parent contact type.</comment>
+ <pseudoconstant>
+ <table>civicrm_contact_type</table>
+ <keyColumn>id</keyColumn>
+ <labelColumn>label</labelColumn>
+ <condition>parent_id IS NULL</condition>
+ </pseudoconstant>
+ <add>3.1</add>