SQL本领:一些非常精良的"SQL"语句[MSSQL防范]

精良的"SQL"语句:

◆复制表(只复制构造,源表名:a 新表名:b)

SQL: select * into b from a where 1<>1

◆拷贝表(拷贝数据,源表名:a 目标表名:b)

SQL: insert into b(a, b, c) select d,e,f from b; 　

◆显示文章、提交人和最后答复时间

SQL: select a.title,a.username,b.adddate from table a,

(select max(adddate) adddate from table where table.title=a.title) b 　

◆阐明:外衔接查询(表名1:a 表名2:b)

SQL: select a.a, a.b, a.c, b.c, b.d, b.f from a LEFT OUT JOIN b ON a.a =

b.c

◆日程安置提早五分钟提醒

SQL: select * from 日程安置 where datediff('minute',f开始时间,getdate())>5 　　

◆两张关联表,删除主表中已经在副表中没有的信息

SQL:

delete from info where not exists

( select * from infobz where info.infid=infobz.infid )

◆阐明:

SQL:

SELECT A.NUM, A.NAME, B.UPD_DATE, B.PREV_UPD_DATE

FROM TABLE1,(SELECT X.NUM, X.UPD_DATE, Y.UPD_DATE

PREV_UPD_DATE FROM (SELECT NUM, UPD_DATE, INBOUND_QTY,

STOCK_ONHAND FROM TABLE2 WHERE TO_CHAR(UPD_DATE,

'YYYY/MM') = TO_CHAR(SYSDATE, 'YYYY/MM')) X,

(SELECT NUM, UPD_DATE, STOCK_ONHAND FROM TABLE2

WHERE TO_CHAR(UPD_DATE,'YYYY/MM') = TO_CHAR(TO_DATE

(TO_CHAR(SYSDATE, 'YYYY/MM') &brVBar;¦ '/01','

YYYY/MM/DD') - 1, 'YYYY/MM') ) Y, WHERE X.NUM = Y.NUM

（+）AND X.INBOUND_QTY + NVL(Y.STOCK_ONHAND,0) <>

X.STOCK_ONHAND ) B WHERE A.NUM = B.NUM

◆阐明:

SQL:

select * from studentinfo where not exists(select * from student where

studentinfo.id=student.id) and 系名称='"&strdepartmentname&"' and 专业名称

='"&strprofessionname&"' order by 性别,生源地,高考总成就. 　　以上是“SQL本领:一些非常精良的"SQL"语句[MSSQL防范]”的内容，如果你对以上该文章内容感兴趣，你可以看看七道奇为您推荐以下文章：