Does this mean that I literally type in 'default_blah' and it will insert "NA" or do I need to be putting 'NA' where 'default_blah' is?

I was hoping for a solution so that if I didn't know what the default value was I could still write a query that would insert the default value if the user hadn't provided one.

- Sorry didn't see the solution offered by graff below before I posted this. Is there a reason why you have used a combination of " and '?

my $sth = $dbh->prepare('INSERT INTO foo SET '
                            . "bar  = isnull(?, 'default_bar'), '
                            . "blah = isnull(?, 'default_blah')) "
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Must admit the mixing of " and ' characters is confusing and when I plug it into my code as is I get some errors.

Bareword found where operator expected at line 442, near ". "blah
"
  (Might be a runaway multi-line "" string starting on line 441) (#1)
    (S syntax) The Perl lexer knows whether to expect a term or an ope
+rator.
    If it sees what it knows to be a term when it was expecting to see
+ an
    operator, it gives you this warning.  Usually it indicates that an
    operator or delimiter was omitted, such as a semicolon.

        (Missing operator before blah?)
Unquoted string "blah" may clash with future reserved word at line 442
+ (#2)
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Line 442 is:

. "blah = isnull(?, 'default_blah')) "
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