devops/postgres/tools/removeUnusedDocuments.sql

   1
   2 WITH repeated AS
   3   ( select nn.node2_id AS id, count(*) AS c
   4     FROM nodes_nodes nn
   5     GROUP BY nn.node2_id
   6   )
   7
   8 DELETE FROM nodes n
   9 USING repeated r
  10 WHERE
  11 n.id = r.id
  12 AND r.c <= 1
  13 ;
  14