指定一个ID找到上下的范围
倒是不复杂
需求:
实现思路:
给定一个ID,比如272944
如果表中的ID大于这个值,则自定义变量自增加一,
如果表中的ID小于这个值,则用这个值减去表中ID,
如果表中的ID等于这个值,则为0
- SELECT
- a.ZpID,
- CASE
- WHEN a.zpid - 272944 > 0 THEN @a:=@a + 1
- WHEN a.zpid - 272944 < 0 THEN a.zpid - 272944
- ELSE 0
- END AS rn
- FROM
- zp_audio_video a, (SELECT @a:=0) vars
- WHERE
- a.State = 1
- AND a.Labels LIKE '三周年站庆歌曲类%'
- ORDER BY a.Zpid
结果:
最后过滤找到结果:
- SELECT
- *
- FROM
- (
- SELECT
- a.ZpID,
- CASE
- WHEN a.zpid - 272944 > 0 THEN @a:=@a + 1
- WHEN a.zpid - 272944 < 0 THEN a.zpid - 272944
- ELSE 0
- END AS rn
- FROM
- zp_audio_video a, (SELECT @a:=0) vars
- WHERE
- a.State = 1
- AND a.Labels LIKE '三周年站庆歌曲类%'
- ORDER BY a.Zpid
- ) a
- WHERE
- rn <= 5 AND rn != 0
- ORDER BY rn DESC
- LIMIT 10;
正文到此结束