(* INDEXES *)
let sprintf_refObj_index name = [
-sprintf "CREATE INDEX %s_index ON %s (source(219),h_occurrence(219),h_position);" name name ]
+sprintf "CREATE INDEX %s_index ON %s (source(219),h_occurrence(219),h_position);" name name;
+sprintf "CREATE INDEX %s_occurrence ON %s (h_occurrence);" name name ]
let sprintf_refSort_index name = [
sprintf "CREATE INDEX %s_index ON %s (source,h_sort,h_position,h_depth);" name name]