server-tools/base_external_dbsource/base_external_dbsource_demo.xml

<?xml version="1.0"?>
<openerp>
    <data>

        <record model="base.external.dbsource" id="demo_postgre">
            <field name="name">PostgreSQL local</field>
            <field name="conn_string">dbname='postgres' password=%s</field>
            <field name="password">postgresql</field>
            <field name="connector">postgresql</field>
        </record>
        
    </data>
</openerp>