ROW_NUMBER() OVER()函数用来为每条记录返回一个行号,可以用来对记录进行排序并返回该序号,序号从1开始排序。...这里的over()是聚集函数,可以给记录进行分组、排序;row_number()不能单独使用,必须搭配over()才能使用,否则会报错。...简单地返回的行号 1 2 给student的每条记录进行排序并返回序号 select *, row_number() over() from student; num class name row_number...1000 1 小明 1 1001 2 小白 2 1002 2 小黑 3 给返回的行号起个别名 1 select *, row_number() over() rank from student;...*, row_number() over(partition by class order by num desc) rank from student; num class name rank 1000
为了排查app端是否存在bug,用到row_number() over () 窗口函数。...row_number over sql如下 select a.gu_id,starttime, row_number() over (partition by gu_id order by starttime...rank() OVER sql如下 select a.gu_id,starttime, rank() OVER (partition by gu_id order by starttime) rn from...0000-0030-ffff-ffffef748aff 1500448202219 14 00000000-0000-0030-ffff-ffffef748aff 1500448202987 15 对比row_number...和 rank() OVER 的结果,可以发现,rank在处理相同的记录时候,编号是一样的,同时编号就不再连续,直到遇到有差异的记录。
知乎主页 row_number 语法 ROW_NUMBER()函数将针对SELECT语句返回的每一行,从1开始编号,赋予其连续的编号。...在查询时应用了一个排序标准后,只有通过编号才能够保证其顺序是一致的,当使用ROW_NUMBER函数时,也需要专门一列用于预先排序以便于进行编号 partition by关键字是分析性函数的一部分,它和聚合函数不同的地方在于它能返回一个分组中的多条记录...原始表score: s_id 表是学生编号,c_id表是课程编号,s_score 表是学生对应的课程分数 1.要求:得出每门课程的学生成绩排序(升序) —-因为是每门课程的结果,并且要排序,所以用row_number...select * ,row_number() over (partition by c_id order by s_score) from score; 返回结果: 2:进一步要求:得出每门课程的学生成绩...,并且按照70分作为分割线排序—即低于70分的排序,高于70分的排序 select * ,row_number() over (partition by c_id,(case when s_score>
语法格式:row_number() over(partition by 分组列 order by 排序列 desc) row_number() over()分组排序功能: 在使用 row_number(...(无分组) select id,name,age,salary,row_number()over(order by salary desc) rn from TEST_ROW_NUMBER_OVER t...rank from TEST_ROW_NUMBER_OVER t 结果: 再一次排序:找出每一组中序号为一的数据 select * from(select id,name,age,salary,row_number...13岁到16岁数据,按salary排序 select id,name,age,salary,row_number()over(order by salary desc) rank from TEST_ROW_NUMBER_OVER...and 后执行的 例二: 1.使用row_number()函数进行编号,如 select email,customerID, ROW_NUMBER() over(order by psd) as rows
使用 ROW_NUMBER() OVER 的写法 -- t_sorted_order_detail:根据 order_id 分组后,再根据 row_num 排序得到的订单流水数据。...SELECT * FROM ( SELECT *, ROW_NUMBER...说明 ROW_NUMBER ( ) OVER ( [query_partition_clause] order_by_clause ) 它的作用是,根据某个字段分组,然后根据字段排序,并拿到排序第一条记录...然后 ROW_NUMBER() OVER 这个函数就会为每条记录返回在分组内排好的序号。...total_cancel_user_day merchant_id 1 1 mechant_1 1 1 merchant_2 2 2 总 以前的我看到会想:分组,GROUP BY 搞定;还要一个总的,另外计算一个总的结果,然后把结果进行 UNION
,并将登录日期减去该编号对应的天数(可以一步到位): SELECT role_id,`date`, DATE_SUB(`date`,INTERVAL (row_number() OVER(PARTITION...FROM( SELECT role_id,`date`, DATE_SUB(`date`,INTERVAL (row_number() OVER(PARTITION BY role_id ORDER..., row_number() OVER (PARTITION BY role_id ORDER BY continuous_days DESC) rk FROM( SELECT role_id...,begin_date,end_date, continuous_days , row_number() OVER (PARTITION BY role_id ORDER BY continuous_days...FROM( SELECT role_id,`date`, DATE_SUB(`date`,INTERVAL (row_number() OVER(PARTITION BY role_id
, row_number() OVER ( PARTITION BY role_id ORDER BY date ASC ) sort FROM ( SELECT DISTINCT role_id...FROM ( SELECT role_id , date , row_number() OVER (PARTITION BY role_id ORDER BY date ASC)...完整代码 SELECT role_id , begin_date , end_date , continuous_days max_continuous_days FROM ( SELECT...* , row_number() OVER (PARTITION BY role_id ORDER BY continuous_days DESC) sort_continuous_days...SELECT role_id , date , row_number() OVER (PARTITION BY role_id ORDER BY
语法:ROW_NUMBER() OVER (PARTITION BY COL1 ORDER BY COL2) 功能:表示根据COL1分组,在分组内部根据 COL2排序,而这个值就表示每组内部排序后的顺序编号...(组内连续的唯一的) row_number() 返回的主要是“行”的信息,并没有排名 --在test表中根据name分组,age进行排序 select name,age,row_number()...over(partition by name order by age desc) from test; --去掉重复的记录 select * from (select name,age,row_number...() over( partition by name order by age desc) rn from test )where rn= 1; 来源:https://blog.csdn.net/farxix
我们先创建一个测试数据表Scores WITH t AS (SELECT 1 StuID,70 Score UNION ALL SELECT 2,85 UNION ALL SELECT 3,85 UNION...ALL SELECT 4,80 UNION ALL SELECT 5,74 ) SELECT * INTO Scores FROM t; SELECT * FROM Scores 结果如下: 1、ROW_NUMBER...1.1 对学生成绩排序 示例 SELECT ROW_NUMBER() OVER (ORDER BY SCORE DESC) AS [RANK],* FROM Scores; (提示:可以左右滑动代码)...结果如下: 这里RANK就是每个学生的排名后的次序, 根据Score进行DESC倒序 1.2 获取第2名的成绩信息 SELECT * FROM ( SELECT ROW_NUMBER() OVER...下面看例子: 示例 SELECT ROW_NUMBER() OVER (ORDER BY SCORE DESC) AS [RANK],* FROM Scores; SELECT RANK() OVER
kcbh) zwh from v_ypz union all select top 30 '002' kcbh,'第2考场' kcmc,30 kcrs,ROW_NUMBER() over(order...by kcbh) zwh from v_ypz union all select top 30 '003' kcbh,'第3考场' kcmc,30 kcrs,ROW_NUMBER() over(...order by kcbh) zwh from v_ypz union all select top 30 '004' kcbh,'第4考场' kcmc,30 kcrs,ROW_NUMBER() over...over(order by kcbh) zwh from v_ypz union all select top 30 '006' kcbh,'第6考场' kcmc,30 kcrs,ROW_NUMBER...top 30 '001' kcbh,'第1考场' kcmc,30 kcrs,ROW_NUMBER() over(order by kcbh) zwh from v_ypz union all select
all select 2 a, 11 b union all select 3 a, 11 b union all select...cnt, rank() over(order by cnt desc) rn from ( select live_id...b, row_number() over(order by b) row_number, rank() over(order by b) rank, dense_rank...() over(order by b) dense_rank from ( select 1 a, 10 b union all select...union all select 7 a, 13 b ) t 结果: a b row_number rank dense_rank 1 10 1
() 实现 select e.* ,row_number() over(partition by deptno order by empno) as ROW_NUMBER from emp e; 2605...SELECT * FROM (SELECT E.*, ROW_NUMBER() OVER(PARTITION BY DEPTNO ORDER BY SAL DESC) AS RN...= deptno,@rn:=@rn+1,@rn:=1) as "ROW_NUMBER() OVER" , @deptno:=deptno,@sal:=sal from (select empno...ROWNUM, ROW_NUMBER() OVER(PARTITION BY TEAM ORDER BY Y) AS RN, ROWNUM...- ROW_NUMBER() OVER(PARTITION BY TEAM ORDER BY Y) AS DIFF FROM NBA E ORDER BY Y) GROUP BY
2017-07-20#Hive Analytics Functions : row_number rank over 在做数据分析是,会统计用户访问app不同页面的开始时间,理论上同一个用户访问不同页面的开始时间应该不同...为了排查app端是否存在bug,用到row_number() over () 窗口函数。...row_number over sql如下 select a.gu_id,starttime, row_number() over (partition by gu_id order by starttime...rank() OVER sql如下 select a.gu_id,starttime, rank() OVER (partition by gu_id order by starttime) rn from...和 rank() OVER 的结果,可以发现,rank在处理相同的记录时候,编号是一样的,同时编号就不再连续,直到遇到有差异的记录。
下面,我们借助开窗函数ROW_NUMBER()实现了INTERSECT ALL的效果: USE WJChi; SELECT ROW_NUMBER() OVER(PARTITION BY Name,...USE WJChi; -- 实现INTERSECT ALL效果 SELECT T.Name,T.Age FROM ( SELECT ROW_NUMBER() OVER(PARTITION...ROW_NUMBER() OVER(PARTITION BY Name,Age ORDER BY Age) AS RowNumber, Name,Age FROM dbo.UserInfo...同样,我们借助开窗函数ROW_NUMBER()来实现EXCEPT ALL效果: USE WJChi; SELECT T.Name,T.Age FROM ( SELECT ROW_NUMBER...SELECT ROW_NUMBER() OVER(PARTITION BY Name,Age ORDER BY Age) AS RowNumber, Name,Age
MIoU(Mean IoU,Mean Intersection over Union,均交并比,交集 / 并集),也就是语义分割中所谓的 Mask IoU 。...(current) ground_truth_set = current.sum(axis=1) predicted_set = current.sum(axis=0) union...= ground_truth_set + predicted_set - intersection IoU = intersection / union.astype(np.float32)
flag1,flag2, it_dept, row_number() over(order by flag2, a,id desc,rn) rn -- 排序显示 from ( select 1...x.*, y.id, row_number()over(partition by x.a order by y.id) rn -- rn用于where条件 from (select...1 id union select 2) y) t -- 笛卡尔积制造2倍的行数 where rn <= cnt+1 -- 每个分区多出一行 union all select 1 flag1...()over(partition by x.a order by y.id) rn from (select a, b, count(*)over(partition by a) cnt...from t2) x, (select 1 id union select 2) y) t where rn <= cnt+1
mid, row_number() over(partition by expose order by expose), row_number() over(partition...by click order by click), row_number() over(partition by order order by order), row_number...from ( select '1' mid, 1 expose ) a group by mid ) t union all select mid,...mid, 1 click ) a group by mid ) t union all select mid, 0 as expose_rn,...) t union all select mid, 0 as expose_rn, 0 as click_rn, 0 as
union all select 802264764 AS employee_id,7000 AS salary_amount union all select 802264765...union all select 802264768 AS employee_id,1000 AS salary_amount union all select...avg(salary_amount)from (select employee_id, salary_amount, row_number() OVER...(order by salary_amount asc) up_rank, row_number() OVER (order by salary_amount desc) desc_rank..., rank() OVER (order by salary_amount asc) up_rank, rank() OVER (order by salary_amount
假设存在表格如下: select 'a' as category, 19 as duration union all select 'b' as category, 15 as duration union...all select 'c' as category, 12 as duration union all select 'd' as category, 53 as duration union all...category ,row_number() over (order by cast(duration as int) desc) duration_rank from (select 'a'...as category, 19 as duration union all select 'b' as category, 15 as duration union all select 'c' as...category, 12 as duration union all select 'd' as category, 53 as duration union all select 'e' as category
, purchase_time, row_number()over(partition by user_id order by purchase_time...asc) as asc_rn from t_order ) t1 where t1.asc_rn =1 union all select order_id, user_id...t2.desc_rn =1 结果 使用union替代union all的结果 方法二: select order_id, user_id, product_id, quantity...product_id, quantity, purchase_time, row_number()over(partition by...user_id order by purchase_time asc) as asc_rn, row_number()over(partition by user_id order