thanks, that's a lot of good info. maybe I can ask you another q :-) I am running this query, and it works fine in mySQL, i.e. md contains the right datetime value in mySQL. however, I don't believe mt is getting assigned md's value 
my $check_inv_sql = "SELECT MAX(cdt) AS md FROM s_i ORDER BY cdt LIMIT
+ 1";

$sth=$dbh->prepare($s_query) or die $dbh->errstr;

$sth->execute;

my $mt;

if (my $hash_ref = $sth->fetchrow_hashref)
{
 $mt = $hash_ref->{'md'};
print "$mt\n";#this returns below error
}

[download]
and the error it generates is 
Use of uninitialized value $mt in concatenation (.) or string at Sb.pl
+ line 56.

[download]
It seems to me that I am not assigning md correctly to $mt. If that is indeed the case, how do I correct the above code....thx!

In reply to Re^6: timestamp in perl by baperl
in thread timestamp in perl by baperl

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