comment on

my $sth = $dbh->prepare("select NAME from data_template_data");
my $results = $sth->execute() or die "execute failed";

# the return value from $sth->execute() will be undef
# if the query failed...otherwise the $results value
# will contain the number of lines in that result set
#
# The DBI will return "0E0" to mean a true value with
# a numeric result of "zero" to differentiate between
# "didn't work" (undef) and "worked, but returned no rows"
# this is the "logically true, but numeric false value".

#To get the rows, use a while() loop..
#

while ( (my $name) = $sth->fetchrow()) 
{
   print "name is $name\n";
}
[download]

I don't know the schema for your DB. But in general, you will get a NULL for for a blank field instead of undef, but there are exceptions. There are "rules" for the fields that are specified when the table is created.

If you can give me some data, I can create a MySQL DB on my server and help you further.
Don't go "crazy", just give me 5-10 lines or so.

In reply to Re: Perl DBI NULL and undef by Marshall
in thread Reaped: Perl DBI NULL and undef by NodeReaper

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