- $sSQL .= 'UPDATE placex SET (wikipedia, importance) = (SELECT wikipedia, importance FROM compute_importance(extratags, country_code, osm_type, osm_id));';
+ $sSQL .= 'UPDATE placex SET (wikipedia, importance) =';
+ $sSQL .= ' (SELECT wikipedia, importance';
+ $sSQL .= ' FROM compute_importance(extratags, country_code, osm_type, osm_id));';
+ $sSQL .= 'UPDATE placex s SET wikipedia = d.wikipedia, importance = d.importance';
+ $sSQL .= ' FROM placex d';
+ $sSQL .= ' WHERE s.place_id = d.linked_place_id and d.wikipedia is not null';
+ $sSQL .= ' and (s.wikipedia is null or s.importance < d.importance);';