再谈 UNION ALL 和 ORDER BY NEWID 一起使用

当使用UNION ALL或者UNION时，如果按照NewId()随机排序，那么，不能直接写
 
SQL 代码
SELECT TOP 2 * FROM [Article] Where ArticleId < 100 Order By NewId()
UNION ALL
SELECT TOP 8 * FROM [Article] Where ArticleId > 200 Order By NewId()
需要写成
 
SQL 代码
SELECT * FROM (SELECT TOP 2 * FROM [Article] Where ArticleId < 100 Order By NewId()) A
UNION ALL
SELECT * FROM (SELECT TOP 8 * FROM [Article] Where ArticleId > 200 Order By NewId()) B
但是，这些，在SQL Server 2008里面是正确的，但在SQL Server2000里面，仍然会报告错误：如果语句中包含UNION 运算符，那么ORDER BY 子句中的项就必须出现在选择列表中。
在SQL Server 2000里面，需要写成
 
SQL 代码
SELECT * FROM (SELECT TOP 2 *, NewId() As RandomX FROM [Article] Where ArticleId < 100 Order By RandomX) A
UNION ALL
SELECT * FROM (SELECT TOP 8 *, NewId() As RandomX FROM [Article] Where ArticleId > 200 Order By RandomX) B
才可以正常执行。