undef does not work the way you think it does:

if(undef($text)) { ...

This will always set a variable to undef. You likely want defined as in if( ! defined($text)) { ...:

foreach my $row (@{$data_all}) { say $row; my %currec = %{$row}; foreach my $columns (keys %currec) { my $text = $currec{$columns}; say $text; if(! defined ($text)) { say "$columns is NOT DEFINED"; } elsif (length($text) < 1) { say "$columns DEFINED, but empty"; } } exit; }

In reply to Re: Can't detect empty Hash from a MySQL table by Corion
in thread Can't detect Hash values that are empty by SergioQ

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