scala - Is it possible to alias columns programmatically in spark sql?

Question

In spark SQL (perhaps only HiveQL) one can do:

select sex, avg(age) as avg_age
from humans
group by sex

which would result in a DataFrame with columns named "sex" and "avg_age".

How can avg(age) be aliased to "avg_age" without using textual SQL?

Edit: After zero323 's answer, I need to add the constraint that:

The column-to-be-renamed's name may not be known/guaranteed or even addressable. In textual SQL, using "select EXPR as NAME" removes the requirement to have an intermediate name for EXPR. This is also the case in the example above, where "avg(age)" could get a variety of auto-generated names (which also vary among spark releases and sql-context backends).

Answer 1

Let's suppose human_df is the DataFrame for humans. Since Spark 1.3:

human_df.groupBy("sex").agg(avg("age").alias("avg_age"))