1 (* Copyright (C) 2000, HELM Team.
3 * This file is part of HELM, an Hypertextual, Electronic
4 * Library of Mathematics, developed at the Computer Science
5 * Department, University of Bologna, Italy.
7 * HELM is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version 2
10 * of the License, or (at your option) any later version.
12 * HELM is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with HELM; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place - Suite 330, Boston,
22 * For details, see the HELM World-Wide-Web page,
23 * http://cs.unibo.it/helm/.
26 let default_connection_string =
27 "dbname=mowgli_test user=helm"
29 let connection = ref None
31 let connection_string =
32 try Sys.getenv "POSTGRESQL_CONNECTION_STRING"
33 with Not_found -> default_connection_string
36 try connection := Some (new Postgres.connection connection_string);
37 with _ -> raise (Failure ("MQIPostgres.init: " ^ connection_string))
39 let close () = match ! connection with
43 let check () = ! connection <> None
45 let exec q = match ! connection with
47 | Some c -> (c#exec q)#get_list
52 let l = String.length s in
53 let i = String.index s '\'' in
54 String.sub s 0 i ^ "\\'" ^ quote_aux (String.sub s (succ i) (l - (succ i)))
57 "'" ^ quote_aux s ^ "'"