SPyQL is really cool and its design is very smart, with it being able to leverage normal Python functions!
As far as similar tools go, if you're interested, I recommend taking a look at DataFusion[0], dsq[1], and OctoSQL[2].
DataFusion is a very (very very) fast command-line SQL engine but with limited support for data formats.
dsq is based on SQLite which means it has to load data into SQLite first, but then gives you the whole breath of SQLite, it also supports many data formats, but is slower at the same time.
OctoSQL is faster, extensible through plugins, and supports incremental query execution, so you can i.e. calculate and display a running group by + count while tailing a log file. It also supports normal databases, not just file formats, so you can i.e. join with a Postgres table.
[0]: https://github.com/apache/arrow-datafusion
[1]: https://github.com/multiprocessio/dsq
[2]: https://github.com/cube2222/octosql
Disclaimer: Author of OctoSQL