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CREATE TABLE student (
id int,
name varchar(128)
);
INSERT INTO student (id,name) VALUES
(1,'John'),
(2,'Bob'),
(3,'Alice'),
(4,'Don'),
(5,'Eve');
5 rows affected
UPDATE s
SET name = CASE WHEN rn % 2 = 0 THEN prevName ELSE nextName END
FROM (
SELECT *,
prevName = LAG(name, 1, name) OVER (ORDER BY id),
nextName = LEAD(name, 1, name) OVER (ORDER BY id),
-- the extra parameters mean you get the current value if there is no next row
rn = ROW_NUMBER() OVER (ORDER BY id)
FROM student
) s
5 rows affected
select * from student
| id | name |
|---|---|
| 1 | Bob |
| 2 | John |
| 3 | Don |
| 4 | Alice |
| 5 | Eve |