In the process of testing various scripts for an upcoming upgrade from perl 5.004 to 5.005_03 and from DBI 0.91 to 1.13, I've run across a glitch in using DBI->quote() on tied elements of hashes.

Specifically, I'm trying to use DBI to automatically quote an element of a hash tied via CGI->Vars: 

use DBI;
use CGI;

$q = new CGI("test=foo");
$p = $q->Vars;
$dbh = DBI->connect("dbi:mysql:test");

print "element is $p->{test}, quoted element is " .
  $dbh->quote($p->{test}) . "\n";

$test = $p->{test};
print "element is $test, quoted element is " .
  $dbh->quote($test) . "\n";

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For some reason, it seems that DBI thinks that its parameter is not defined() and returns NULL. I've tried this with NDBM_File as well and experienced the same behavior.

Strangely enough, if you try tracing the DBI handle at level 2 or higher, it works just fine: 

DBI->trace(2, 'dbitrace.log');

[download]

Is there something I can do to use the tied hash elements without constant copying them out, and without slowing down for full tracing?

In reply to DBI-quote doesn't like tied hashes? by RSevrinsky

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