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
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SELECT
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a.ZpID,
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WHEN a.zpid - 272944 > 0 THEN @a:=@a + 1
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WHEN a.zpid - 272944 < 0 THEN a.zpid - 272944
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ELSE 0
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END AS rn
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FROM
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zp_audio_video a, (SELECT @a:=0) vars
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WHERE
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a.State = 1
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AND a.Labels LIKE '三周年站庆歌曲类%'
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ORDER BY a.Zpid
结果:
最后过滤找到结果:
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SELECT
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*
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FROM
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(
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SELECT
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a.ZpID,
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WHEN a.zpid - 272944 > 0 THEN @a:=@a + 1
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WHEN a.zpid - 272944 < 0 THEN a.zpid - 272944
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ELSE 0
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END AS rn
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FROM
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zp_audio_video a, (SELECT @a:=0) vars
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WHERE
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a.State = 1
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AND a.Labels LIKE '三周年站庆歌曲类%'
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ORDER BY a.Zpid
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) a
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WHERE
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rn <= 5 AND rn != 0
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ORDER BY rn DESC
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LIMIT 10;
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