脚本宝典收集整理的这篇文章主要介绍了一些实用的sql语句,脚本宝典觉得挺不错的,现在分享给大家,也给大家做个参考。
1.查询高于平均价格的商品名称:
SELECT
ITem_n
ame
From ebsp.
PRoduct_market_price WHERE item_price > (SELECT AVG(item_price) F
rom ebsp.product_market_price
2.
oracle9i以上版本,可以实现将某张表的数据同时插入到多张表中。例:
INSERT ALL
WHEN deptno=10 THEN INTO dept10 --
部门编号为10的插入表dept10中
WHEN deptno=20 THEN INTO dept20
WHEN deptno=30 THEN INTO dept30
WHEN job='CLERK' THEN INTO clerk --岗位为CLERK的插入表clerk 中
ELSE INTO other
SELECT * FROM em
p; 可以将前面的
SQL语句变为INSERT
First 后面不变,当使用First操作符执行多表插入时,如果数据已经满足了先前的条件,并且已经被插入到某表中,那么该行数据
在后续的插入中将不会被再次使用。
3.截取字符串制定的长度。
@H_
777_24@
select s
ubstr(item_name,0,2) from ebsp.product_market_price
select substr(‘ho鲜红的鲜花 ',0,3) from dual; --print ‘ho鲜'
SQL1: select * from scott.emp where hiredate in (select hiredate mycount from scott.emp
group by hiredate having count(*) >1)
SQL2:select t2.* from scott.emp t2 ,
(select t.hiredate,count(*) mycount from scott.emp t group by t.hiredate having count(*) >1) t1
where t2.hiredate = t1.hiredate
alter system set db_cache_size = 700m sco
PE = spfile;
alter system set shared_pool_size = 200m scope=spfile;
alter system set pga_aggregate_t
arget = 100m scope=spfile;