top N percent (),
with ties order by,top ,
distinct 2.Count()
count(*) ,avg,max,min,sum
3.Group by ,:,,Having group by where ,where,having.
4.RCube Compute Compute by 5. : 1 inner join 2 on :select distinct (lastname+' '+firstname) as name,orderid from employees as e inner join orders as o on e.employeeid=o.employeeid
:,:table1,table1table2,table2Table1 left join table2 on expression
Table1 left outer join table2 on expression
:table2,table2table1,table1Table1 right join table2 on expression
Table1 right outer table2 on expression
:,.
Table1 full join table2 on expression
Table1expression
:where,table1,table2,Table1 cross join table2
6.Union [all],all
.
7.
DML,.32,,.
:
,where.
,.
先外层查询再内层查询再外层再内层
:select lastname,firstname from employees as e where '1998-1-1' in (select orderdate from orders as o where o.employeeid=e.employeeid)
exists(not exists),,true ,false
:select lastname,firstname from employees as e where exists (select * from orders as o where o.employeeid=e.e.employeeid and o.orderdate='1998-1-1')
where.
,.
:select lastname,firstname from employees where employeesid in (select employeesid from orders where orders.orderdate='1998-1-1')
子查询可以作为派生的?/p>
可以作ؓ表达?/p>
Select productname,unitprice,(unitprice-(select avg(unitprice) from products) ) as diff from products where productname='chai'
模拟联接子句
having
N之狼的java之旅 2006-10-09 14:21 发表评论
]]>N之狼的java之旅 2006-06-26 14:44 发表评论
]]>01. 不说"不可?三个?
02. 凡事W一反应:找方?而不是找借口.
03. 遇到挫折对自己大声说:太棒?
04. 不说消极的话,不落入消极情l?一旦出现立x面处理
05. 凡事先订立目?q且量制作"梦想?.
06. 凡事预先作计?量目标视觉化.
07. 工作旉.每一?每一U都做有利于生的事?
08. 随时用零的旉(如等人、排队等)做零的事情.
09. 守时.
10. 写下?不要太依靠脑袋记?
11. 随时记录灉|.
12. 把重要的观念,Ҏ写下?q脓h,以随时提C?
13. 走\比^时快30%,走\时脚稍用力推进,肢体语言健康有力,不懒 ?萎靡.
14. 每天出门照镜?l自׃个自信的微笑.
15. 每天自我反省一?
16. 每天坚持一ơ运?
17. 听心跳一分钟,指在做重要事情前,疲劳?心情烦躁?紧张?
18. 开会坐在前?
19. 微笑.
20. 用心們,不打断对方说?
21. 说话时声x?感觉自己声音g能生有感染力的场.
22. 说话之前,先考虑一下对方的感受.
23. 每天有意?真诚地赞别Zơ以?
24. 及时写感谢卡,哪怕是用便W写.
25. 不用训斥,指责的口吻跟别h说话.
26. 控制住不要让自己做出p护的W一反应.
27. 每天做一?分外?.
28. 不管M斚w,每天必须臛_做一?q步一点点".
29. 每天提前15分钟上班,推迟30分钟下班.
30. 每天在下班前? 分钟的时间做一天的整理工作.
31. 定期存钱.
32. 节P.
33. 时常q用"头脑风暴".
34. 恪守诚信,说到做到.
35. I am the best One!!!
N之狼的java之旅 2006-06-24 19:34 发表评论
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