Exception on search with Drupal Commons and Postgresql

I have a problem with facetapi search on Drupal Commons 7.

PDOException: SQLSTATE[42803]: Grouping error: 7 ERROR: column "n.changed" must appear in the GROUP BY clause or be used in an aggregate function LINE 3: (SELECT n.changed AS value ^: SELECT r.value AS value, count AS count, COUNT(r.value) AS count FROM (SELECT n.changed AS value FROM {search_index} i INNER JOIN {node} n ON n.nid = i.sid INNER JOIN {search_total} t ON i.word = t.word INNER JOIN {search_dataset} d ON i.sid = d.sid AND i.type = d.type WHERE (n.status = :db_condition_placeholder_0) AND (n.changed >= :db_condition_placeholder_1) AND (n.changed < :db_condition_placeholder_2) AND( (i.word = :db_condition_placeholder_3) )AND (i.type = :db_condition_placeholder_4) AND( (d.data ILIKE :db_condition_placeholder_5) ) GROUP BY i.type, i.sid HAVING (COUNT(*) >= :matches) ) r GROUP BY r.value ORDER BY count DESC; Array ( [:db_condition_placeholder_0] => 1 [:db_condition_placeholder_1] => 1453736103 [:db_condition_placeholder_2] => 1453826103 [:db_condition_placeholder_3] => test [:db_condition_placeholder_4] => node [:db_condition_placeholder_5] => % test % [:matches] => 1 ) inFacetapiFacetProcessor->initializeBuild() (line 1482 of /projet/src/website/drupal/profiles/commons/modules/contrib/facetapi/plugins/facetapi/adapter.inc)