
Wishlist for sqldf package



- test out package with MySQL (code is already there)

- improve explanation in sqldf.Rd

- more examples (only if they truly add something since we already have
  quite a few)


These depend on software outside of sqldf:

- MySQL supports sign(), var_pop(), variance(), var_samp(), std() and 
  stddev_samp() functions but SQLite does not.

- neither MySQL nor SQLite supports median() or quantile()

- if database driver not specified through argument or option then
  MySQL is used if RMySQL package is loaded and SQLite is used otherwise.
  This is a bit fragile and it would be better if we could check that
  the MySQL driver (rather than package) had actually been loaded.  Note 
  that currently there is no way to check this but if RMySQL and DBI were 
  upgraded to support such discovery this feature could be added.

- there has been some talk about removing the automatic dot to undescore 
  conversion in the DBI layer that underlies both RSQLite and RMySQL.  If
  that were to be done then sqldf would have to be modified accordingly.

