top3salariesbydepartment.pig

# load the raw data

raw = load 'emp.txt' using PigStorage('\t') as (empno:int,ename:chararray,job:chararray,sal:int,deptno:int);

# group the raw data by deptno.  There are only 3 departments(10,20,30)
grpd = group raw by deptno; 

# for each deptno(grpd), sort the data by sal in descending order, then limit
# to 3 rows and return the output.

top3sal =            
  foreach grpd
    {ordered = order raw by sal desc;
     limited = limit ordered 3;
     generate flatten(limited.(sal,ename,empno,deptno));
    }