Narveson:

A couple notes: First, if you want to convert an empty string to a null on the insert, you shouldn't consider the map statement as an argument against placeholders. After all, you'll have to perform the conversion in *any* method you use. It's a different issue entirely.

Second, if you're considering an empty string as an illegal value in your database, you might consider using a stored procedure to perform your inserts, and enforce it there, so your various perl scripts don't all have to do the checking. Something like:

create sproc insert_foo @bar as varchar(77)
as
    if @bar = ''
        set @bar=null
    insert into foo (bar) values (@bar)
[download]

(Or use the nullif function, etc.)

...roboticus