How MySQL table of tree structure sum?-CodePudding

A table is as follows:

 DROP TABLE IF the EXISTS ` t_test `; 
The CREATE TABLE ` t_test ` (
` Id ` int (11) NOT NULL, 
` ParentId ` int (11) NULL DEFAULT NULL, 
` Qty ` int (11) NULL DEFAULT NULL, 
` Qty_Sum ` int (11) NULL DEFAULT NULL, 
PRIMARY KEY (` Id `) USING BTREE 
) ENGINE=InnoDB CHARACTER SET=utf8 COLLATE=utf8_general_ci ROW_FORMAT=Compact; 

-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
- Records of t_test 
-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
INSERT INTO ` t_test ` VALUES (1, 0, 1, 0); 
INSERT INTO ` t_test ` VALUES (2, 1, 2, 0); 
INSERT INTO ` t_test ` VALUES (3, 2, 3, 0); 
INSERT INTO ` t_test ` VALUES (4, 3, 4, 0); 
INSERT INTO ` t_test ` VALUES (5, 1, 5, 0); 

The SET FOREIGN_KEY_CHECKS=1;

Hope to be able to in a flexible way to find the tree structure (hierarchy multi-stage uncertainty) of each level, and achieve results in the table below (Qty_Sum as the summation of the results) :

 
Id ParentId Qty Qty_Sum 
1 0 1 15 
2 1 2 9 
3, 2, 3, 7 
4, 3, 4, 4 
5 1 5