query implem

solution.pl

@@ -316,10 +316,125 @@ selec/4 predicate.
 For “INSERT”, nothing needs to be printed by query/1 or in case of
 success, and if query/2 is used the Result parameter can be ignored.
 */
-/* query(Query, Result). */ 
+query(Query, Result):-
+	parse_query(Query, Fun, Args),
+	apply(Fun, Args),
+	last(Args, Result).
+
+/**
+ * Parse SELECT * FROM <table> WHERE <conds>
+*/
+parse_query(Query, selec, [AtomTable, *, AtomsConds, R]):-
+	split_string(Query, " ", ",;+", SplitQuery),
+	append(["SELECT"], L1, SplitQuery),
+	append(["*"], ["FROM"|L2], L1),
+	append([Table], ["WHERE"|Conds],L2),
+	atom_string(AtomTable, Table),
+	maplist(parse_cond, AtomsConds, Conds),!.
+/**
+ * Parse SELECT <cols> FROM <table> WHERE <conds>
+*/
+parse_query(Query, selec, [AtomTable, AtomsSelectors, AtomsConds, R]):-
+	split_string(Query, " ", ",;+", SplitQuery),
+	append(["SELECT"], L1, SplitQuery),
+	append(Selectors, ["FROM"|L2], L1),
+	append([Table], ["WHERE"|Conds],L2),
+	atom_string(AtomTable, Table),
+	maplist(atom_string, AtomsSelectors1, Selectors),
+	maplist(add_plus, AtomsSelectors, AtomsSelectors1),
+	maplist(parse_cond, AtomsConds, Conds),!.
+
+/**
+ * Parse SELECT * FROM <table>
+*/
+parse_query(Query, selec, [AtomTable, *, R]):-
+	split_string(Query, " ", ",;+", SplitQuery),
+	append(["SELECT"], L1, SplitQuery),
+	append(["*"], ["FROM",Table], L1),
+	atom_string(AtomTable, Table),
+	maplist(parse_cond, AtomsConds, Conds),!.
+
+/**
+ * Parse SELECT <cols> FROM <table>
+*/
+parse_query(Query, selec, [AtomTable, AtomsSelectors, R]):-
+	split_string(Query, " ", ",;+", SplitQuery),
+	append(["SELECT"], L1, SplitQuery),
+	append(Selectors, ["FROM",Table], L1),
+	atom_string(AtomTable, Table),
+	maplist(atom_string, AtomsSelectors1, Selectors),
+	maplist(add_plus, AtomsSelectors, AtomsSelectors1).
+	
+parse_query(Query, insert, [AtomTable, Values]):-
+	split_string(Query, " ", '",();', SplitQuery),
+	append(["INSERT", "INTO"], L1, SplitQuery),
+	L1 = [Table | L2],
+	append(_, ["VALUES"|Values], L2),
+	atom_string(AtomTable, Table).
+
+add_plus(+A, A).
+
+% parse >= conditon
+parse_cond(+AtomLeft>=AtomRight, Cond):-
+	string_chars(Cond, Code),
+	append(LeftMemb, [>,=|RightMemb], Code),
+	string_chars(Left, LeftMemb),
+	string_chars(Right1, RightMemb),
+	split_string(Right1,"",'"',[Right]),
+	atom_string(AtomLeft, Left),
+	is_number(AtomRight, Right),!.
+
+% parse <= conditon
+parse_cond(+AtomLeft<=AtomRight, Cond):-
+	string_chars(Cond, Code),
+	append(LeftMemb, [<,=|RightMemb], Code),
+	string_chars(Left, LeftMemb),
+	string_chars(Right1, RightMemb),
+	split_string(Right1,"",'"',[Right]),
+	atom_string(AtomLeft, Left),
+	is_number(AtomRight, Right),!.
+
+% parse < conditon
+parse_cond(+AtomLeft<AtomRight, Cond):-
+	string_chars(Cond, Code),
+	append(LeftMemb, [<|RightMemb], Code),
+	string_chars(Left, LeftMemb),
+	string_chars(Right1, RightMemb),
+	split_string(Right1,"",'"',[Right]),
+	atom_string(AtomLeft, Left),
+	is_number(AtomRight, Right),!.
+
+% parse > conditon
+parse_cond(+AtomLeft>AtomRight, Cond):-
+	string_chars(Cond, Code),
+	append(LeftMemb, [>|RightMemb], Code),
+	string_chars(Left, LeftMemb),
+	string_chars(Right1, RightMemb),
+	split_string(Right1,"",'"',[Right]),
+	atom_string(AtomLeft, Left),
+	is_number(AtomRight, Right),!.
+
+% parse = conditon
+parse_cond( +AtomLeft=AtomRight, Cond):-
+	string_chars(Cond, Code),
+	append(LeftMemb, [=|RightMemb], Code),
+	string_chars(Left, LeftMemb),
+	string_chars(Right1, RightMemb),
+	split_string(Right1,"",'"',[Right]),
+	atom_string(AtomLeft, Left),
+	is_number(AtomRight, Right),!.
+
+is_number(R, N):-
+	atom_number(N, R); R = N.
+
 
 :- dynamic query/1.
 /*
 cf. query/2
 */
-/* query(Query). */ 
+
+query(Query) :-
+    query(Query, R),
+    writeln(R),
+    fail.
+query(_).