syntax.ml

   1 (* SQL syntax and RA *)
   2
   3 open Stmt.Raw
   4 open Operators
   5
   6 type expr = | Value of Sql.Type.t
   7             | Param of Stmt.Raw.param
   8             | Sub of expr list
   9             | Column of string * string option (** name, table *)
  10             deriving (Show)
  11
  12 type column =
  13   | All
  14   | AllOf of string
  15   | Expr of expr * string option (** name *)
  16   deriving (Show)
  17
  18 type columns = column list deriving (Show)
  19
  20 let collect f l = List.flatten (List.map f l)
  21
  22 let get_scheme columns tables =
  23   let all = tables >> List.map snd >> List.flatten in
  24   let scheme name = name >> Tables.get_from tables >> snd in
  25   let resolve1 = function
  26     | All -> all
  27     | AllOf t -> scheme t
  28     | Expr (e,name) ->
  29       let col =
  30       begin match e with
  31       | Column (name,Some t) -> RA.Scheme.find (scheme t) name
  32       | Column (name,None) -> RA.Scheme.find all name
  33       | _ -> RA.attr "" Sql.Type.Text
  34       end in
  35       let col = Option.map_default (fun n -> {col with RA.name = n}) col name in
  36       [ col ]
  37   in
  38   collect resolve1 columns
  39
  40 let get_params e =
  41   let rec loop acc e =
  42     match e with
  43     | Param p -> p::acc
  44     | Sub l -> List.fold_left loop acc l
  45     | _ -> acc
  46   in loop [] e
  47
  48 (*
  49 let _ =
  50   let e = Sub [Value Sql.Type.Text; Param (Next,None); Sub []; Param (Named "ds", Some Sql.Type.Int);] in
  51   e >> get_params >> to_string >> print_endline
  52 *)
  53
  54 let params_of_column = function
  55   | All | AllOf _ -> []
  56   | Expr (e,_) -> get_params e
  57
  58 let params_of_columns = collect params_of_column
  59
  60 let get_params_opt = function
  61   | Some x -> get_params x
  62   | None -> []
  63
  64 let get_params_l = collect get_params
  65