sql查询文章上一篇下一篇

遇到显示文章时显示上一篇、下一篇的id、title提示需求,经常就是取到当前文章,然后再根据发布时间分别取到上一篇、下一篇文章,然是这样要交互三次数据库,想写一个sql一次执行出来,原来写的是

SELECT
    *,
    beforeId = ( SELECT TOP 1 id FROM Articles WHERE PublishTime > ( SELECT PublishTime FROM Articles WHERE id = 'c703b010-7218-4e99-b76a-4603ea65f16f' ) ORDER BY PublishTime ),
    beforeTitle = ( SELECT TOP 1 Title FROM Articles WHERE PublishTime > ( SELECT PublishTime FROM Articles WHERE id = 'c703b010-7218-4e99-b76a-4603ea65f16f' ) ORDER BY PublishTime ),
    afterId = ( SELECT TOP 1 id FROM Articles WHERE PublishTime < ( SELECT PublishTime FROM Articles WHERE id = 'c703b010-7218-4e99-b76a-4603ea65f16f' ) ORDER BY PublishTime DESC ),
    afterTitle = ( SELECT TOP 1 Title id FROM Articles WHERE PublishTime < ( SELECT PublishTime FROM Articles WHERE id = 'c703b010-7218-4e99-b76a-4603ea65f16f' ) ORDER BY PublishTime DESC ) 
FROM
    Articles 
WHERE
    id = 'c703b010-7218-4e99-b76a-4603ea65f16f'

有四个子查询,后来经人指点,查出上一篇后直接把它的id,title拼接一下就行了,省了一次子查询

--- 更进一步的用法:使用字符串拼接
SELECT
    *,
    before = ( SELECT TOP 1 (convert(varchar(36),id)+'|'+Title) as aa FROM Articles WHERE PublishTime > ( SELECT PublishTime FROM Articles WHERE id = '0F6CFE90-AC48-42CE-98A0-59F9195A95B2' ) ORDER BY PublishTime ),
    after = ( SELECT TOP 1 (convert(varchar(36),id)+'|'+Title) FROM Articles WHERE PublishTime < ( SELECT PublishTime FROM Articles WHERE id = 'c703b010-7218-4e99-b76a-4603ea65f16f' ) ORDER BY PublishTime DESC )
FROM
    Articles 
WHERE
    id = '0F6CFE90-AC48-42CE-98A0-59F9195A95B2'

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转载自blog.csdn.net/qq_34720759/article/details/79739838