Spark sql group by和求和更改列名称？

Question

In this data frame I am finding total salary from each group. In Oracle I'd use this code

select job_id,sum(salary) as "Total" from hr.employees group by job_id;

In Spark SQL tried the same, I am facing two issues

empData.groupBy($"job_id").sum("salary").alias("Total").show()

1. The alias total is not displaying instead it is showing "sum(salary)" column

2. I could not use $ (I think Scala SQL syntax). Getting compilation issue

     empData.groupBy($"job_id").sum($"salary").alias("Total").show() 

Any idea?

Answer 1

Use Aggregate function .agg() if you want to provide alias name. This accepts scala syntax ($" ")

empData.groupBy($"job_id").agg(sum($"salary") as "Total").show()

If you dont want to use .agg() , alias name can be also be provided using .select() :

empData.groupBy($"job_id").sum("salary").select($"job_id", $"sum(salary)".alias("Total")).show()