| Subject: | output bound parameters may be incorrectly bound if changed after bind_param_inout |
This issue is in 1.39 and probably most versions of DBD::ODBC back to
when deferred binding was removed (and it was only for MS SQL Server
anyway). It cropped up on perl monks at
http://perlmonks.org/?node_id=989136.
The following code fails. Output expected and actual output below:
my $dbh = DBI->connect;
my @cols = qw(foo bar);
my $sql = <<SQL;
SELECT :foo, :bar
SQL
my $sth = $dbh->prepare($sql);
my %hsh;
for (@cols) {
$sth->bind_param_inout( "$_" => \$hsh{$_}, 0 );
}
Dump($hsh{foo});
# Set constants...
#Dump($hsh{foo});
$hsh{foo} = 'abc';
#$hsh{foo} .= "aaa";
# Set changing values
#Dump($hsh{bar});
$hsh{bar} = 123;
#Dump($hsh{bar});
Dump($hsh{foo});
$sth->execute();
while (my @arr = $sth->fetchrow_array) {
print "@arr\n";
}
$hsh{bar} = 456;
$sth->execute();
while (my @arr = $sth->fetchrow_array) {
print "@arr\n";
}
$dbh->disconnect();
Actual output:
Use of uninitialized value $arr[0] in join or string at /tmp/x.pl line 33.
123
Use of uninitialized value $arr[0] in join or string at /tmp/x.pl line 39.
456
Expected output:
abc 123
abc 456
Martin
--
Martin J. Evans
Wetherby, UK