Re: Supporting non-free SQL clients in ob-sql (was: [PATCH] ob-sql: Add support for Athena)

[Tim Cross]

Ihor Radchenko <yantar92@posteo.net> writes:

> Tim Cross <theophilusx@gmail.com> writes:
>
>> to be very clear, ob-sql is not adding any NEW interface to any external
>> program. It is just using the Emacs built-in SQL library (Elisp), which
>> has been part of Emacs for a long time (I was using it in late 90s to
>> work with Oracle RDMS). It is this library that provides the 'support'
>> for things like Oracle's RDMS. If you want more specific information,
>> ask on emacs-devel. Org mode is just using this built-in library.
>
> This is wrong.
> `org-babel-execute:sql' directly calls the CLI executable via `process-file'.
>
> That said, the discussion about sql.el is also relevant wrt non-free SQL
> client support. It will be helpful to clarify what is morally acceptable
> for all the scenarios, not just for Org's use-case.
>
>> The Oracle database is simply a relational database management system in
>> the same way as Postgres, MySQL, Ingris, MS-Sql server etc. All of these
>> have a CLI client and support connections via JDBC. The sql.el library
>> provides specialised comint based interfaces which run the CLI to
>> communicate with the RDMS. The closest of your 3 choices is b, as the
>> build-in Emacs sql library executes the RDMS CLI in a sub-process comint
>> buffer.
>
> Org does not use this comint interface yet. We may in future though, for
> sessions:
>
> (defun org-babel-prep-session:sql (_session _params)
>   "Raise an error because Sql sessions aren't implemented."
>   (error "SQL sessions not yet implemented"))

OK, thanks the for correction. I was confused because the set of
supported RDBMS is the same as those supported by sql.el and the
connection credentials uses the same variable name
i.e. sql-connection-alist.

However, I gues the point remains, sql.el and ob-sql.el support a number
of non-free RDMS and I think this is fine given that

1. There is no encouragement, implicit or explicit, to use a non-free
database
2. Provided support provides a way to interact with these non-free RDMS using
free software.
3. There is no requirement to install non-free software to use
ob-sql.el. The software is fully functional using a free RDMS like
postgres.

For maintenance reasons and to add session support, I would suggest that
using sql.el instead of re-inventing this wheel would be a better
outcome. I've used sql.el for years and it works extremely well and I
don't htink it would be too hard to integrate into ob-sql.