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精妙地sql語句:

◆復(fù)制表(只復(fù)制結(jié)構(gòu),源表名：a 新表名：b)

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

◆拷貝表(拷貝數(shù)據(jù),源表名：a 目標表名：b)

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

◆顯示文章、提交人和最后回復(fù)時間

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

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

◆說明：外連接查詢(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

◆日程安排提前五分鐘提醒

sql: select * from 日程安排 where datediff('minute',f開始時間,getdate())>5 　　

◆兩張關(guān)聯(lián)表，刪除主表中已經(jīng)在副表中沒有地信息

sql:

delete from info where not exists

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

◆說明：

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;&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

◆說明：

sql:

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

studentinfo.id=student.id) and 系名稱='&strdepartmentname&' and 專業(yè)名稱

='&strprofessionname&' order by 性別,生源地,高考總成績

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