SELECT RDB$RELATIONS.RDB$RELATION_NAME,
CASE 
WHEN RDB$INDICES.RDB$STATISTICS = 0 THEN 0 
ELSE CAST(1 / RDB$INDICES.RDB$STATISTICS AS INTEGER) 
END 
FROM RDB$RELATIONS 
LEFT JOIN RDB$RELATION_CONSTRAINTS 
 ON RDB$RELATIONS.RDB$RELATION_NAME = RDB$RELATION_CONSTRAINTS.RDB$RELATION_NAME 
 AND RDB$CONSTRAINT_TYPE = 'PRIMARY KEY'
LEFT JOIN RDB$INDICES 
  ON RDB$RELATION_CONSTRAINTS.RDB$INDEX_NAME = RDB$INDICES.RDB$INDEX_NAME 
WHERE RDB$VIEW_BLR IS NULL AND RDB$RELATION_ID >= 128 
ORDER BY 1;
