How do I query for content that has not been updated (no revisions)?
Content that has not been updated would only have one revision, so you could count the number of revisions and use a having condition.

First you'll have to join the node_revision table to the node table

$query-&gt;leftJoin('node_revision', 'r', 'n.nid = r.nid');


Count the number of revisions

$query-&gt;addExpression('COUNT(n.nid)', 'revision_count');


Filter rows with a revision_count higher than 1

$query-&gt;havingCondition('revision_count', 1, '&lt;=');