sql精妙用法.docx

sql精妙用法SQLSERVER 2010-12-22 13:18:40 阅读112 评论0 ??字号：大中小?订阅说明：复制表(只复制结构,源表名：a 新表名：b) select * into b from a where 11 说明：拷贝表(拷贝数据,源表名：a 目标表名：b)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)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select * from 日程安排 where datediff(minute,f开始时间,getdate())5 说明：两张关联表，删除主表中已经在副表中没有的信息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：-- 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）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, S