一道面试题，求答案

Question

[img]http://dl.iteye.com/upload/attachment/544376/ade1565c-8baf-39f1-96ea-7badc4aa50e4.jpg[/img]
具体问题如下图，求解答，谢谢！

Answer 1

你这个可能是要你写一个外链接
orcle代码：
[code="sql"]
select a.id,a.name,b.type,decode(b.id,null,'N','Y') uitl from a表 a left join b表 b on a.id=b.id;
[/code]

sql2005
orcle代码：
[code="sql"]
select a.id,a.name,b.type,case when b.id is null then 'N' else 'Y' end uitl from a表 a left join b表 b on a.id=b.id;
[/code]