oracle排名函数的使用方法分享
编程学习 2021-07-05 16:08www.dzhlxh.cn编程入门
本文介绍下,oracle中排名函数的用法,通过实例学习oracle排名函数的具体用法,有需要的朋友可以参考下
在oracle中,有rank,dense_rank,row_number,以及分组排名partition。
说明:
rank:排名会出现并列第n名,它之后的会跳过空出的名次,例如:1,2,2,4
dense_rank:排名会出现并列第n名,它之后的名次为n+1,例如:1,2,2,3
row_number:排名采用唯一序号连续值,例如1,2,3,4
partition:将排名限制到某一分组
格式:
row_number() over(partition by bb.channel_name order by sum(aa.dk_serv_num) desc nulls last) p1_rank1,
row_number() over(order by sum(aa.dk_serv_num) desc nulls last) rank1,
dense_rank() over(order by nvl(sum(aa.dk_serv_num), 0) desc) rank2,
rank() over(order by sum(aa.dk_serv_num) desc nulls last) rank3
例子:
procedure GetCompetitionRanking(p_UserId in integer, p_CompetitionId in integer, v_cursor out CompetitionCursor) is v_startDate date; v_endDate date; tmp_startDate varchar2(12); tmp_endDate varchar2(12); tmp_date date; v_sql1 varchar2(2000); v_sql2 varchar2(2000); v_where varchar2(1000); v_comTotal integer; v_groupTotal integer; v_comRanking integer; v_groupRanking integer; begin select t.start_date, t.end_date into v_startDate, v_endDate from tbl_competition t where t.competition_id = p_CompetitionId; tmp_date:= v_endDate+1; tmp_startDate := to_char(v_startDate, 'yyyy-mm-dd'); tmp_endDate := to_char(tmp_date, 'yyyy-mm-dd'); --group personal total select count(1) into v_groupTotal from tbl_com_group_user a where a.com_group_id in ( select b.com_group_id from tbl_com_group_user b where b.user_id = p_UserId ); -- Competition personal total select count(1) into v_comTotal from ( select a.com_group_id from tbl_com_group a where a.competition_id = p_CompetitionId ) a inner join tbl_com_group_user b on a.com_group_id = b.com_group_id; --user in competition ranking and group ranking v_where := 't.DATA_TYPE_ID=1 AND t.STATUS=1 AND t.DATA_DATE_1 >= TO_DATE('||chr(39)||tmp_startDate||chr(39)||','||chr(39)||'yyyy-mm-dd'||chr(39)||') AND t.DATA_DATE_1 < TO_DATE('||chr(39)||tmp_endDate||chr(39)||','||chr(39)||'yyyy-mm-dd'||chr(39)||') '; /*select no from ( select a.USER_ID, dense_rank() over(order by sum(nvl(DATA_NUMBER_2, 0)) desc) no from ( select user_id from tbl_com_group a left join tbl_com_group_user b on a.com_group_id = b.com_group_id where a.competition_id = 1 ) a left join VM_MASTER_DATA t on a.user_id = t.user_id and t.DATA_TYPE_ID=1 AND t.STATUS=1 AND t.DATA_DATE_1 >= TO_DATE('2012-10-02','yyyy-mm-dd') AND t.DATA_DATE_1 < TO_DATE('2012-12-01','yyyy-mm-dd') group by a.user_id order by no desc ) where user_id = 165*/ v_sql1 := 'select no from ( select a.USER_ID, dense_rank() over(order by sum(nvl(DATA_NUMBER_2, 0)) desc) no from ( select user_id from tbl_com_group a left join tbl_com_group_user b on a.com_group_id = b.com_group_id where a.competition_id = '||p_CompetitionId||' ) a left join VM_MASTER_DATA t on a.user_id = t.user_id and '|| v_where||' group by a.user_id order by no desc ) where user_id = '||p_UserId; dbms_output.put_line(v_sql1); execute immediate v_sql1 into v_comRanking; dbms_output.put_line('------------------------------'); --dbms_output.put_line(v_comRanking); /*select no from ( select a.USER_ID, dense_rank() over(order by sum(nvl(DATA_NUMBER_2, 0)) desc) no from ( select a.user_id from tbl_com_group_user a where a.com_group_id in ( select b.com_group_id from tbl_com_group_user b where b.user_id = 165 ) ) a left join VM_MASTER_DATA t on a.user_id = t.user_id and t.DATA_TYPE_ID=1 AND t.STATUS=1 AND t.DATA_DATE_1 >= TO_DATE('2012-10-02','yyyy-mm-dd') AND t.DATA_DATE_1 < TO_DATE('2012-12-01','yyyy-mm-dd') group by a.user_id order by no desc ) where user_id=165*/ v_sql2 := 'select no from ( select a.USER_ID, dense_rank() over(order by sum(nvl(DATA_NUMBER_2, 0)) desc) no from ( select a.user_id from tbl_com_group_user a where a.com_group_id in ( select b.com_group_id from tbl_com_group_user b where b.user_id = '||p_UserId||' ) ) a left join VM_MASTER_DATA t on a.user_id = t.user_id and '|| v_where||' group by a.user_id order by no desc ) where user_id = '||p_UserId; dbms_output.put_line(v_sql2); execute immediate v_sql2 into v_groupRanking; --dbms_output.put_line('------------------------------'); --dbms_output.put_line(v_groupRanking); if v_comRanking is null then v_comRanking := v_comTotal; end if; if v_groupRanking is null then v_groupRanking := v_groupTotal; end if; open v_cursor for select v_comTotal CompetitionPersonalTotal, v_groupTotal UserInGroupPersonTotal, v_comRanking UserInCompRanking, v_groupRanking UserInGroupRanking from dual; exception when others then null; end;