negative constant instead of unary operation

mindsdb/mindsdb#7118

mindsdb_sql/parser/dialects/mindsdb/parser.py

@@ -1314,6 +1314,10 @@ def expr(self, p):
     def expr(self, p):
         return UnaryOperation(op=p[0], args=(p.expr,))
 
+    @_('MINUS constant %prec UMINUS')
+    def constant(self, p):
+        return Constant(-p.constant.value)
+
     # update fields list
     @_('update_parameter',
        'update_parameter_list COMMA update_parameter')

mindsdb_sql/planner/utils.py

@@ -44,12 +44,12 @@ def recursively_extract_column_values(op, row_dict, predictor):
         id = op.args[0]
         value = op.args[1]
 
-        if (
-            isinstance(value, UnaryOperation)
-            and value.op == '-'
-            and isinstance(value.args[0], Constant)
-        ):
-            value = Constant(-value.args[0].value)
+        # if (
+        #     isinstance(value, UnaryOperation)
+        #     and value.op == '-'
+        #     and isinstance(value.args[0], Constant)
+        # ):
+        #     value = Constant(-value.args[0].value)
 
         if not (
                 isinstance(id, Identifier)

tests/test_parser/test_mindsdb/test_selects.py

@@ -109,3 +109,15 @@ def test_join_using(self):
 
         assert str(ast) == str(expected_ast)
         assert ast.to_tree() == expected_ast.to_tree()
+
+    def test_select_limit_negative(self):
+        sql = """SELECT * FROM t1 LIMIT -1"""
+
+        ast = parse_sql(sql, dialect='mindsdb')
+        expected_ast = Select(targets=[Star()],
+                              from_table=Identifier(parts=['t1']),
+                              limit=Constant(-1))
+
+        assert ast.to_tree() == expected_ast.to_tree()
+        assert str(ast) == str(expected_ast)
+