** should this throw an error for no variable definition
   :PROPERTIES:
   :DATE:     2011-09-15
   :END:
Evaluating this block should raise an error that there are
uninitialized variables.

#+name: add-column-in-table(table="", column="", something, type="", else, nullability)
#+begin_src sql
-- add column `$column' (if column does not exist yet)
IF NOT EXISTS (SELECT *
               FROM INFORMATION_SCHEMA.COLUMNS
               WHERE TABLE_NAME = '$table'
               AND COLUMN_NAME = '$column')
BEGIN
    ALTER TABLE $table
    ADD $column $type $nullability
END
#+end_src