Re: Re(2): (Ovid): uninitialized value in concatenation

In this

my $name = undef;

# store subparent for each parent
my %parent_hash = ( 'Father' => 'Mother',
                    'Mother' => 'Father' );

if (exists $parent_hash{$parent}) {
  my $sub_parent = $parent_hash{$parent};

  for my $col ( $parent, $sub_parent ) {
    my $sql = "select $col from Roster where User=?";

    my $rv = $dbh->selectcol_arrayref( $sql, undef, $user );
    if ( @$rv ) {  # any rows returned?
      $name = $rv->[0];  # take first one
      last;
    }
  }
}
# here, $name will be defined if one of above succeeded
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what is the undef do inside the

my $rv = $dbh->selectcol_arrayref( $sql, undef, $user );
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Comment on Re: Re(2): (Ovid): uninitialized value in concatenation Select or Download Code

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Re(4): (Ovid): uninitialized value in concatenation by dmmiller2k (Chaplain) on Jan 15, 2002 at 20:00 UTC
From the `DBI` docs: `selectrow_array @row_ary = $dbh->selectrow_array($statement); @row_ary = $dbh->selectrow_array($statement, \%attr); @row_ary = $dbh->selectrow_array($statement, \%attr, @bind_values);` [download] where the third form is the one I was using, without specifying any attributes (i.e., `undef`). dmm If you GIVE a man a fish you feed him for a day But, TEACH him to fish and you feed him for a lifetime	[reply] [d/l] [select]
Re(4): (Ovid): uninitialized value in concatenation by dmmiller2k (Chaplain) on Jan 15, 2002 at 20:01 UTC
From the `DBI` docs: `selectrow_array @row_ary = $dbh->selectrow_array($statement); @row_ary = $dbh->selectrow_array($statement, \%attr); @row_ary = $dbh->selectrow_array($statement, \%attr, @bind_values);` [download] where the third form is the one I was using, without specifying any attributes (i.e., `undef`). dmm	[reply] [d/l] [select]