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 ) FROMArticles WHEREid = '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 )FROMArticles WHEREid = '0F6CFE90-AC48-42CE-98A0-59F9195A95B2'
