Dear monks, I'd like to ask for help understanding this problem.

The context is a mod_perl Apache http server and DBI access to mysql.

The action of an html form is a perl handler. The handler starts off by getting the request object and reading an identifying cookie: 

sub handler {
my $r = Apache2::Request->new(shift);
my %in_cookies = Apache2::Cookie->fetch ($r);
my $session = $in_cookies{"ID"} && $in_cookies{"ID"}->value;
...

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The handler takes arguments from $r->param and writes them to a mysql table by means of a database handle obtained from DBI->connect.

The problem: it has occurred at least once that data from one call to the handler has persisted to the next and has been written to a record belonging to a different session. Specifically, this section of code misfired, the hash %ship_address somehow retaining data from its previous assignment: 

while ( my ($key,$value) = each %ship_address ) {
   $dbh->do("update bill set ship$key = ? where session = ?", undef, $
+value, $session);

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The 2nd customer was very surprised to learn he lived on the 5th floor of a one story house...

I am uncertain how to isolate the problem. Can you help? Thanks.

In reply to keeping variables separate by RandomWalk

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