oracle數(shù)據(jù)庫(kù)字段是否區(qū)分大小寫 ORACLE怎么寫先排序后分組的前5位?
ORACLE怎么寫先排序后分組的前5位?先把ORDERED的順序搞出來(lái)就行了select *from (select a.*,row_number() over(partition by ordere
ORACLE怎么寫先排序后分組的前5位?
先把ORDERED的順序搞出來(lái)就行了
select *
from (select a.*,
row_number() over(partition by ordered order by cdate desc) px,
max(cdate) over(partition by ordered) sqrt_id
from (select a.*, b.user_name username
from view_hjzx a, gjjx.sys_users b
where a.userid = b.userid( )
and a.HANDSET like "901054535%") a)
where px
order by sqrt_id desc, cdate desc
oracleSQL用select過(guò)程進(jìn)行分組排序查詢?
實(shí)現(xiàn)思路:通過(guò)select進(jìn)行查詢,通過(guò)group by進(jìn)行分組后,之后通過(guò)order by進(jìn)行排序。sql:select username from tablename order by username desc group by username以上就是通過(guò)username字段降序排序(升序是ASC、降序是DESC)。
oracle里面怎么多個(gè)字段分組排序?
select a,b,c from table
group by a,b,c
order by a,b,c asc
order by 后面哪個(gè)字段在前面就是先按哪個(gè)字段排序(順序asc 降序 desc)
oracle有空值的分組排序問(wèn)題?
直接排序做不到的,要么
1、列2排序、列1排序,如此列2能達(dá)到要求,但列1滿足不了
2、或者對(duì)列2不空列1為空的行的列1置成某行相同的列1,排序,然后展示的時(shí)候?qū)α?重置成空
oracle里面怎么多個(gè)字段分組排序?
分組排序用group by,若需要條件則在后面加having。多個(gè)字段的話用order by,比如:order by a,border by 可以讓表按a排序,遇到重復(fù)的再按b再排一次序,做到把想要的字段與其他無(wú)關(guān)字段分開比較。