$ perl -wE'
use DBI;
my $dbh = DBI->connect(...);
$dbh->do("set wait_timeout=5");
my $sth = $dbh->prepare_cached("SELECT COUNT(*) FROM ...");
$sth->execute or die $dbh->errstr;
say $sth->fetchrow_array;
sleep 6;
$sth->execute or die $dbh->errstr;
say $sth->fetchrow_array;
'
0
DBD::mysql::st execute failed: MySQL server has gone away at -e line 9.
MySQL server has gone away at -e line 9.