GDL2 and data source in a file

[stefan]

Hello,

Is it possible to use plain files (CSV or something similar) as data sources in
GDL2? For example, I have a file with following columns:

    step, agent_id, agent_type, energy, path_length, action

Say each element is an integer. I wat to get this:

SELECT agent_type, avg(energy) FROM table_from_file GROUP BY agent_type

1. how do i tell GDL2 that i want to use a file? (if that is possible)
2. how do i specify the file structure?
3. how do i prepare the above select statement?

(1b: is it possible to combine more tables from more files in a single query?)

This is just very simple example, and of course, it can be done much easier by
other ways for this case. Other query requests are going to be much more
complicated. Sources may vary from file to database.

Thanks,

Stefan Urbanek