relational operators added

parser.h

@@ -91,19 +91,26 @@ struct  DatabaseValueNode : Node {
     DatabaseValueNode(std::string name) : Node(NodeType::database_value), col_name(name) {}
 };
 
+enum class LogicalOperatorType {
+    and_operator,
+    or_operator,
+    not_operator
+};
+
 struct LogicalOperatorNode : Node {
-//    and_operator,
-//    or_operator,
-//    not_operator,
-    // and / or / not
+    LogicalOperatorType  op;
     std::unique_ptr<Node> left;
     std::unique_ptr<Node> right;
 };
 
 enum class RelationalOperatorType {
     equal,
-    greater
-    // =, !=, >, >=, <, <=, like
+    greater,
+    greater_equal,
+    lesser,
+    lesser_equal,
+    not_equal
+    // like
 };
 
 struct RelationalOperatorNode : Node {