Oracle SQL座位交换练习题答案分享

Oracle SQL练习题39题的答案，题目要求交换每两个连续学生的座位号，并按id升序返回结果表。如果学生数量为奇数，则最后一个学生的id不交换。SQL语句如下： SELECT CASE WHEN MOD(id,2)=1 AND id=(SELECT COUNT(*) FROM seat) THEN id WHEN MOD(id,2)=1 THEN id+1 ELSE id-1 END id,student FROM seat ORDER BY id; SELECT RANK() OVER(ORDER BY (CASE WHEN MOD(id,2)=0 THEN id-1 ELSE id+1 END)) id,student FROM seat;