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0. 说明

　　Hive 的分析函数 窗口函数  | 排名函数 | 最大值 | 分层次 | lead && lag 统计活跃用户 | cume_dist

 

 

 

 

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1. 窗口函数(开窗函数) over

　　1.1 说明

　　1 preceding　　//前一个

　　1 following　　//后一个

　　current row　　//当前行

　　unbounded preceding　　//无上限

　　unbounded following　　//无下限

　　1.2 测试

# 以行定义窗口界限select id, name, age , sum(age)over(order by id rows between current row and 2 following) from user_par;# 以值定义窗口界限select id, name, age , sum(age)over(order by age range between current row and 10 following) from user_par;

 

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2. 排名函数

　　2.1 并列跳跃

　　113

　　rank

select id, name, province, age , rank()over(partition by province order by age desc) from user_par;

 

　　2.2 不跳跃

　　112

　　dense_rank

select id, name, province, age , dense_rank()over(partition by province order by age desc) from user_par;

 

　　2.3 顺序

　　123

　　row_number

select id, name, province, age , row_number()over(partition by province order by age desc) from user_par;

 

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3. 最大值

　　first_value()

select id, name, province, age , first_value()over(partition by province order by age desc) from user_par;

 

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4. 分层次

　　按照三六九等进行平均分层

　　ntile()

select id, name, age , ntile(3)over(order by age desc) from user_par;

 

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5. lead && lag

　　5.1 lead()

　　将列向上提

select id, name, province, age , lead(age)over(partition by province order by age asc) from user_par;

 

　　5.2 lag()

　　将列向下沉

select id, name, province, age , lag(age)over(partition by province order by age asc) from user_par;

 

　　5.3 统计连续活跃

　　1. 准备数据

　　

 

　　2. 建表

create table active(id string, month int) row format delimitedfields terminated by '\t';

 

　　3. 加载数据

load data local inpath '/home/centos/files/active.txt' into  table active;

 

　　4. 统计连续两月活跃用户

select id from (select id, month, lead(month)over(partition by id order by month desc) as month2 from active)a where month=month2+1;

 

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6. cume_dist()

　　指定值占总数的百分比

 

　　Demo

select id,name,age, cume_dist()over(order by age desc) from user_nopar;

 　　

 

 

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