-module(mnesia_test).
-export([setup_and_start/0, insert/2, retrieve/1, search/1, search_qlc/1]).

-include("/usr/lib/erlang/lib/stdlib-1.16.2/include/qlc.hrl").

-record(data, {key, value}).

setup_and_start() ->
    mnesia:create_schema([node()]),
    mnesia:start(),
    mnesia:create_table(data, [{disc_copies, [node()]}, {attributes, record_info(fields, data)}]).

insert(Key, Val) ->
    Record = #data{key = Key, value = Val},
    F = fun() ->
		mnesia:write(Record)
	end,
    mnesia:transaction(F).

retrieve(Key) ->
    F = fun() ->
		mnesia:read({data, Key})
	end,
    {atomic, Data} = mnesia:transaction(F),
    Data.

search_qlc(Val) ->
    F = fun() ->
		qlc:eval(
		  qlc:q(
		    [X || X <- mnesia:table(data), X#data.value == Val]
		   ))
	end,
    {atomic, Data} = mnesia:transaction(F),
    Data.

search(Val) ->
    F = fun() ->
		mnesia:match_object(#data{key = '_', value = Val})
	end,
    {atomic, Data} = mnesia:transaction(F),
    Data.