(* AUTOR: Ferruccio Guidi <fguidi@cs.unibo.it>
*)
-type connection = Mysql.dbd
+let init () =
+ let module HR = Helm_registry in
+ let host =
+ HR.get_opt HR.get_string "mathql_interpreter.mysql_connection.host" in
+ let database =
+ HR.get_opt HR.get_string "mathql_interpreter.mysql_connection.database" in
+ let user =
+ HR.get_opt HR.get_string "mathql_interpreter.mysql_connection.user" in
+ let port =
+ HR.get_opt HR.get_int "mathql_interpreter.mysql_connection.port" in
+ let password =
+ HR.get_opt HR.get_string "mathql_interpreter.mysql_connection.password" in
+ try Mysql.quick_connect ?host ?database ?user ?port ?password ()
+ with _ -> raise (Failure "mqi_connecion")
-let init connection_string =
- try
- Some
- (Mysql.quick_connect
- ~host:"mowgli.cs.unibo.it" ~database:"mowgli" ~user:"helm" ())
- with _ -> raise (Failure ("MQIPostgres.init: " ^ connection_string))
+let close c = Mysql.disconnect c
-let close = function
- | None -> ()
- | Some c -> Mysql.disconnect c
-
-let exec c q = match c with
- | None -> []
- | Some c ->
- Mysql.map
- ~f:(function a ->
- List.map
- (function
- None -> raise (Failure ("NULL found in a table"))
- | Some v -> v
- ) (Array.to_list a)
- ) (Mysql.exec c q)
-
let quote s =
let rec quote_aux s =
try
with Not_found -> s
in
"'" ^ quote_aux s ^ "'"
+
+let exec (c, out) q =
+ let g = function None -> "" | Some v -> v in
+ let f a = List.map g (Array.to_list a) in
+ out q; Mysql.map ~f:f (Mysql.exec c q)
+
+let exec c table cols ct cfl =
+ let rec iter f last sep = function
+ | [] -> last
+ | [head] -> f head
+ | head :: tail -> f head ^ sep ^ iter f last sep tail
+ in
+ let pg_cols = iter (fun x -> x) "" ", " cols in
+ let pg_msval v = iter quote "" ", " v in
+ let pg_con (pat, col, v) =
+ if col <> "" then
+ let f s = col ^ " regexp " ^ quote ("^" ^ s ^ "$") in
+ if pat then "(" ^ iter f "0" " or " v ^ ")"
+ else match v with
+ | [s] -> col ^ " = " ^ (quote s)
+ | v -> col ^ " in (" ^ pg_msval v ^ ")"
+ else "1"
+ in
+ let pg_cons l = iter pg_con "1" " and " l in
+ let pg_cons_not l = "not (" ^ pg_cons l ^ ")" in
+ let pg_cons_not_l ll = iter pg_cons_not "1" " and " ll in
+ let pg_where = match ct, cfl with
+ | [], [] -> ""
+ | lt, [] -> " where " ^ pg_cons lt
+ | [], llf -> " where " ^ pg_cons_not_l llf
+ | lt, llf -> " where " ^ pg_cons lt ^ " and " ^ pg_cons_not_l llf
+ in
+ if cols = [] then
+ let r = exec c ("select count(source) from " ^ table ^ pg_where) in
+ match r with
+ | [[s]] when int_of_string s > 0 -> [[]]
+ | _ -> []
+ else
+ exec c ("select " ^ pg_cols ^ " from " ^ table ^ pg_where ^
+ " order by " ^ List.hd cols ^ " asc")