SQL每日一题(20231207)

CREATE TABLE G1207 (
RKEY int,
Type varchar(20) ,
PARENT_PTR int,
)

INSERT INTO G1207 VALUES(26949,'l1-l8',0);
INSERT INTO G1207 VALUES(26950,'l1-l4',26949);
INSERT INTO G1207 VALUES(26951,'l5-l8',26949);
INSERT INTO G1207 VALUES(26952,'l1-l2',26950);
INSERT INTO G1207 VALUES(26953,'l3-l4',26950);
INSERT INTO G1207 VALUES(26954,'l5-l6',26951);
INSERT INTO G1207 VALUES(26955,'l7-l8',26951);