Re^6: timestamp in perl

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!

Comment on Re^6: timestamp in perl Select or Download Code

Replies are listed 'Best First'.
Re^7: timestamp in perl by Util (Priest) on Sep 25, 2011 at 00:31 UTC
It would help to know whether the key `{'md'}` is missing from the hash, or the key exists but the value undefined. Also, what else is in the hash? What output do you get with this change? `# ... same code as above use Data::Dumper; $Data::Dumper::Useqq = 1; if ( my $hash_ref = $sth->fetchrow_hashref ) { print Dumper $hash_ref; }` [download]	[reply] [d/l] [select]
Re^8: timestamp in perl by baperl (Sexton) on Sep 25, 2011 at 02:37 UTC
my apologies....I was preparing and executing the wrong query as you'll notice in my code....the marvels of copy and paste. your code on the Data::Dumper is helpful, so thanks for that....it'll save me trouble in the future :-)	[reply]