精妙地sql语句:
◆复制表(只复制结构,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、提交人和最后回复时间
sql: select a.title,a.username,b.adddate from table a,
(select max(adddate) adddate from table where table.title=a.title) b
◆说明：外连接查询(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
◆日程安排提前五分钟提醒
sql: select * from 日程安排 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地信息
sql:
delete from info where not exists
( select * from infobz where info.infid=infobz.infid )
◆说明：
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') ¦¦ '/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
◆说明：
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,高考总成绩
更多信息请查看IT技术专栏
