six month dormancy test

source data:

accountleg    year_month    amount
acc1A    2010-01    100
acc1A    2010-02    100
acc1A    2010-03    100
acc1A    2010-04    100
acc1A    2010-06    100
acc1A    2010-07    100
acc1A    2010-08    100
acc1A    2010-09    100
acc1A    2010-10    100
acc1A    2010-11    100
acc1A    2011-06    100
acc1A    2011-07    100
acc1A    2011-08    100
acc1A    2011-09    100
acc1A    2011-10    100
acc1A    2011-11    100
acc1A    2011-12    100
acc1A    2012-01    100
acc1A    2012-07    100

create table sixdormancy (accountleg string,year_month string,amount double) row format delimited fields terminated by '	';
load data local inpath '/mnt/data/sixdormancy.txt' into table sixdormancy;
--get the last row year_month
drop table sixdormancy_lastmonth;
create table sixdormancy_lastmonth as 
select 
*,
lag(year_month) over(partition by accountleg order by year_month) as  lastmonth
from sixdormancy;

create table sixdormancy_monthdiff as 
select *,
(year(concat(year_month,'-01')) - year(concat(lastmonth,'-01')))*12
+month(concat(year_month,'-01'))-
month(concat(lastmonth,'-01')) as monthdiff
from sixdormancy_lastmonth;

select accountleg from sixdormancy_monthdiff where monthdiff>5 group by accountleg;

if 0.10 not support lag function, we can write one udf to do this, and then we can combine
the calculation and filter and the udf.

package myudf;

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;

import org.apache.hadoop.hive.ql.exec.UDF;

public class dormancy extends UDF {

    String accountleg = "";
    String predate = "";
    boolean isDormancy = false;

    public boolean evaluate(String _accountleg, String _date) {
　　　　isDormancy=false;
        if (accountleg.equalsIgnoreCase(_accountleg)) {
            isDormancy = hasSixMonthsGap(predate, _date);
        }
        accountleg = _accountleg;
        predate = _date;
        return isDormancy;
    }

    boolean hasSixMonthsGap(String _sd, String _bd) {
        // issue yyyy-MM
        int year1 = Integer.parseInt(_bd.substring(1, 4));
        int year2 = Integer.parseInt(_sd.substring(1, 4));
        int month1 = Integer.parseInt(_bd.substring(5, 7));
        int month2 = Integer.parseInt(_sd.substring(5, 7));
        int cp = (year1 - year2) * 12 + (month1 - month2) + 1;
        if (cp > 7) // has dormancy
            return true;
        else
            return false;
    }

    public static void main(String[] args) {

        dormancy test = new dormancy();
        // read data from source
        String filepath = "/mnt/data/sixdormancy.txt";
        try {
            BufferedReader br = new BufferedReader(new FileReader(filepath));
            String line;

            line = br.readLine();
            String[] items = null;
            while (line != null) {
                // handle this line data
                items = line.split("	");
                System.out.print(line);
                System.out.print("	");
                System.out.println(test.evaluate(items[0], items[1]));
                line = br.readLine();
            }

        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } catch (Exception ex) {
            ex.printStackTrace();
        }

    }

}

add jar /home/hadoop/workspace/myudf/bin/myudf.jar;
create temporary function dormancy as "myudf.dormancy";
select *,dormancy(accountleg,year_month) from 
(select * from sixdormancy distribute by accountleg sort by accountleg, year_month) a;