I've been experimenting with a generic log parser for Drill. The basic concept is that if you wanted Drill to ingest log files such as this MySQL log:
You probably could do it with the various string manipulation methods such as split, substring etc. but you'd end up with some ugly and very complex queries.
The extension I've built allows you to supply Drill with a regex for the formatting and a list of fields as shown below.
You can then query this log files in this format in Drill. I'd like to submit this for inclusion in Drill if there is interest.