精妙SQL語句
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1. 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;
2. 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;
3. 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 max(adddate) adddate
from table where table.title=a.title) b
4. 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;
5. 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, getdate())>5
6. 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 info.infid=infobz.infid );
7. 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;
8. 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;
SQL: select * into b from a where 1<>1;
2. 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;
3. 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 max(adddate) adddate
from table where table.title=a.title) b
4. 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;
5. 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, getdate())>5
6. 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 info.infid=infobz.infid );
7. 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;
8. 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;