Hi.

I have been playing a bit with org babel, the goal being to be able to
query a recfile[1] and insert the result as a rec table.  Thanks to the
superb design of org-babel and the existing examples, I quickly wrote
the attached little hack.

The hack allows to query a rec file 'foo.rec' as follows:

#+begin_src rec :data hackers.rec :fields Name,Email :type Hacker
Papers = 'requested' && CreatedAt << '01 January 2011'
#+end_src

Where :data points to the recfile (or list of files), :fields is a
comma-separated list of fields (allowing subscripts) and :type selects
the record set where to make the query. :cmdline can also be used to
specify any other command line option to recsel.  All parameters but
:data are optional.

The selection expression can be any expression allowed by recsel in the
-e command line option.

Of course you have to install the recutils for it to work.

It roughly works and I want to add more functionality, but due to my
lack of experience with org-babel I would like to ask some questions
before continuing working on it.

- Is there a way to execute empty code blocks?  It would be quite common
  to require all the records stored in a record set, e.g.

  #+begin_src rec :data inventory.rec
  #+end_src

  C-cC-c in that block echoes "Local setup has been refreshed" and
  nothing happens.  A workaround would be to use a selection expression
  that always evaluates to "true", such as:

  #+begin_src rec :data inventory.rec
  1
  #+end_src

  but it would be nice to avoid it.

- Is there a way to dinamically change the value of the :results
  parameter in the org-babel-execute:rec function?  I would like to add
  a :template parameter containing a template for recfmt, and in that
  case the default value "raw" would not be appropriate.

Thanks in advance :)

[1] http://www.gnu.org/software/recutils