[Versa] More on literal queries

[Chimezie Ogbuji]

 > I agree.  See the new spec (did anyone get this?),

I did, but I'm still absorbing the EBNF difference.  

> it covers this
> (though maybe not really clear).  There is a difference between a
> literal, and a literal query.
> 
> I thought of it more in the case of "concat('a','b')"
> 
> The difference is
> 
> " 'foo' "
> 
> Is a literal query, where the results is a set only if the literal
> exists in the DB and
> 
> " contains('foo') "

The difference wasn't so clear.  Maybe it should be spelled out more
explicitely?