I came across the selectall_hashref by way of some advice I recieved on a previous post.
It looks like something that might work for a script I am writing.
I am trying to test it and learn exactly how it works.
I wrote this code 
my ($k, $v);
my %data_all;
my $dbh =  DBI->connect('DBI:Sybase:#####', '#####', '#####', { RaiseE
+rror => 1, AutoCommit => 1});
my $sql = "select Col1, Col2, Col3 from TABLE where Col4 = 1";
my $data_all = $dbh->selectall_hashref($sql, 1);

while ( ($k,$v) = each %data_all ) {
    print "$k => $v\n";
}

[download]
I get this error.

DBI::st=HASH(0x1027b0)->_prepare(...): attribute parameter '1' is not a hash ref at /nms/site/perl-5.6.0/lib/site_perl/5.6.0/sun4-solaris/DBD/Sybase.pm line 95.

The document I read said that the second parameter is "the column to use as key, indicated by position".
I want Col1 to be the key.

In reply to selectall_hashref by mnlight

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