When calling $sth->fetchrow_array in a scalar context, you're going to get back an array ref, possibly containing some other array refs (your result rows). So your test, if ($name eq "") {, should probably look more like, if ($name->[0][0] eq "") {, except that this completely disregards the case where no rows are returned.

You might also factor out all of the common code and elminate unnecessary complexity:

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

# etc. ...

[download]

Also, why are you using prepared statements (e.g., prepare() and execute()) without placeholders ('?'). You can just call selectrow_arrayref($sql) (or in your case, selectcol_arrayref($sql) since the results will be a single column) to the same effect.

Update: added placeholders, as per cfreak. What was I thinking?

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

In reply to Re(2): (Ovid): uninitialized value in concatenation by dmmiller2k
in thread uninitialized value in concatenation by mnlight

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