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[49878] 主题: 精妙SQL语句 |
作者: leaflet (Leaf) | ||
标题: 精妙SQL语句[转载] | ||
来自: 218.80.*.* | ||
发贴时间: 2003年04月17日 13:32:50 | ||
长度: 3468字 | ||
详细的请看原贴 ^_^
说明: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 说明: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; 说明: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 ma x(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 说明: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,g etdate())>5 说明: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 i nfo.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(SYSDAT E, '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.S TOCK_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='"&strdepa rtmentname&"' and 专业名称='"&strprofessionnam e&"' order by 性别,生源地,高考总成绩 说明: 从数据库中去一年的各单位电话费统计(电话费定额贺电化肥清单两个表来 源) SQL: SELECT a.userper, a.tel, a.standfee, TO_CHAR(a.telfeedate, 'yyyy ') AS telyear, SUM(decode(TO_CHAR(a.telfeedate, 'mm'), '01', a.factration )) AS JAN, SUM(decode(TO_CHAR(a.telfeedate, 'mm'), '02', a.factration )) AS FRI, SUM(decode(TO_CHAR(a.telfeedate, 'mm'), '03', a.factration )) AS MAR, SUM(decode(TO_CHAR(a.telfeedate, 'mm'), '04', a.factration )) AS APR, SUM(decode(TO_CHAR(a.telfeedate, 'mm'), '05', a.factration )) AS MAY, SUM(decode(TO_CHAR(a.telfeedate, 'mm'), '06', a.factration )) AS JUE, SUM(decode(TO_CHAR(a.telfeedate, 'mm'), '07', a.factration )) AS JUL, SUM(decode(TO_CHAR(a.telfeedate, 'mm'), '08', a.factration )) AS AGU, SUM(decode(TO_CHAR(a.telfeedate, 'mm'), '09', a.factration )) AS SEP, SUM(decode(TO_CHAR(a.telfeedate, 'mm'), '10', a.factration )) AS OCT, SUM(decode(TO_CHAR(a.telfeedate, 'mm'), '11', a.factration )) AS NOV, SUM(decode(TO_CHAR(a.telfeedate, 'mm'), '12', a.factration )) AS DEC FROM (SELECT a.userper, a.tel, a.standfee, b.telfeedate, b.factr ation FROM TELFEESTAND a, TELFEE b WHERE a.tel = b.telfax) a GROUP BY a.userper, a.tel, a.standfee, TO_CHAR(a.telfeedate, 'yy yy') 说明:四表联查问题: SQL: select * from a left inner join b on a.a=b.b right inner jo in c on a.a=c.c inner join d on a.a=d.d where ..... 说明:得到表中最小的未使用的ID号 SQL: SELECT (CASE WHEN EXISTS(SELECT * FROM Handle b WHERE b.HandleID = 1) THEN MIN(HandleID) + 1 ELSE 1 END) as HandleID FROM Handle WHERE NOT HandleID IN (SELECT a.HandleID - 1 FROM Handle a) |
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