Rumah  >  Artikel  >  pangkalan data  >  快速掌握一些异常精妙的SQL语句

快速掌握一些异常精妙的SQL语句

黄舟
黄舟asal
2017-02-20 11:43:121076semak imbas

[导读]   精妙的"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 1a8093152e673feb7aba1828c435320941   ◆拷贝表(拷贝数据,源表名:a 目标表名:b) SQL: insert into b(a, b, c) se

  精妙的"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(&#39;minute&#39;,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 )

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,&#39;YYYY/MM&#39;) = TO_CHAR(SYSDATE, &#39;YYYY/MM&#39;))
 X, (SELECT NUM, UPD_DATE, STOCK_ONHAND FROM TABLE2 WHERE TO_CHAR(UPD_DATE,&#39;YYYY/MM&#39;) = TO_CHAR(TO_DATE(TO_CHAR(SYSDATE, &#39;YYYY/MM&#39;)
  &brvbar;&brvbar; &#39;/01&#39;,&#39;YYYY/MM/DD&#39;) - 1, &#39;YYYY/MM&#39;) ) 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=&#39;"&strdepartmentname&"&#39; and 专业名称=&#39;"&strprofessionname&"&#39; order by 性别,生源地,高考总成绩

 以上就是 快速掌握一些异常精妙的SQL语句的内容,更多相关内容请关注PHP中文网(www.php.cn)!


Kenyataan:
Kandungan artikel ini disumbangkan secara sukarela oleh netizen, dan hak cipta adalah milik pengarang asal. Laman web ini tidak memikul tanggungjawab undang-undang yang sepadan. Jika anda menemui sebarang kandungan yang disyaki plagiarisme atau pelanggaran, sila hubungi admin@php.cn