rank,dense_rank,row_number，以及分组排名partition
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
Eg：
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;