On 04-Sep-2006 Tim Bunce wrote:
> file: $CPAN/authors/id/T/TI/TIMB/DBI_AdvancedTalk_200608.pdf
> size: 486540 bytes
> md5: c305fe9ae393a534f17efc83a4563d28
>
> Slides for this years version of my Advanced DBI tutorial are available
> online.
>
> Tim.
Thanks for that - very interesting I certainly noted a couple of things I
wasn't always doing.
It did raise an issue where I could do with some clarification. The slides say:
Execute a statement for multiple values
$sth = $dbh->prepare("insert into table (foo,bar) values (?,?)");
$tuples = $sth->execute_array(\%attr, [EMAIL PROTECTED], [EMAIL PROTECTED]);
returns count of executions (even ones that failed) and not rows-affected.
but the latest DBI pod says:
The execute_array() method returns the number of tuples executed,
or "undef" if an error occured. Like execute(), a successful exe-
cute_array() always returns true regardless of the number of tuples
executed, even if it's zero. See the "ArrayTupleStatus" attribute
below for how to determine the execution status for each tuple.
I read that latter as if undef is returned 1 or more of the executes failed but
now I read in the slides they suggest I may get a true value when an error
occurs. My experience with execute_array and Oracle shows I get:
return 0, when none resulted in a change but no errors
e.g.
drop table mytest
create table mytest (a int primary key, b char(20))
insert into mytest values (1,'onetwothree')
update mytest set b = ? where a = ?
$sth->bind_param_array(2, [2])
$sth->bind_param_array(1, ['two'])
$sth->execute_array( { ArrayTupleStatus => [EMAIL PROTECTED] } )
returns 0
No, error, just no update occurred. It does not return 1 as the slide
suggests and does seem to be the number of rows changed - none.
returns undef when there is an error
e.g.
as per above example but the bind_param_array for p2 is invalid e.g. 'xxx'
This seems to also contradict the slide but agrees with the DBI pod.
lastly I get undef if there are multiple rows but the last one errors.
e.g. as above except the bind_param_arrays are:
$sth->bind_param_array(2, [1, 'xxx']);
$sth->bind_param_array(1, ['one', 'two']);
returns undef but executes the 1,'one'.
I am now unclear as to what is correct. Can you clarify?
Martin
--
Martin J. Evans
Easysoft Ltd, UK
http://www.easysoft.com
