On Wed, Mar 29, 2006 at 09:02:43PM +0100, Martin J. Evans wrote:
> Thanks Tim. I'm now hopefully looking in the right places.
>
> Not seeing execute on a selectrow_array threw me initially
> but it is an example of the problems I'm seeing.
>
> I'm having a few problems accessing things at the time I want.
>
> e.g. execute_array can be called with the parameters (which I
> want to see) and this is ok, but can also be called with
> bind_param_array then execute_array but in this case
> sth->{Params} does not contain the parameters after the
> sth->SUPER::execute_array call (I was suprised by that).
Looking at the code for bind_param_array I see the bound refs are
stored in $sth->{ParamArrays}.
> This is a problem for me since I want to examine the
> tuple_status passed to execute_array and find the
> parameters for the execute which failed. I've found another
> way around this for now by moving the code which highlights
> the parameters which failed into execute.
I'd accept a doc patch to document the ParamArrays attribute.
> Just to put some context on this I'm suclassing DBI as something
> like DBIx::Log4Perl where all the SQL, parameters, fetched data,
> transactions, error handler can be logged. I'm doing this because I
> have a large Perl server accepting a huge number of jobs per second
> which is very transaction heavy. It is impossible to debug since
> it is almost impossible to reproduce the condition which caused the
> error so I need as much info as possible at the time of the problem
> and I need it as light weight as I can make it because slowing it
> down sometimes hides the problem.
Sounds interesting.
Tim.
> Martin
>
> Tim Bunce wrote:
> >On Wed, Mar 29, 2006 at 04:49:32PM +0100, Martin J. Evans wrote:
> >
> >>Tim,
> >>
> >>Thanks, I do keep forgetting about Driver.xst.
> >>
> >>So, just to be clear. In DBI.pm, selectrow_array calls _do_selectrow which
> >>calls prepare/execute/fetchsomething but this may be overriden by a driver
> >>using selectrow_array in Driver.xst. If this is the case:
> >>
> >>a) is there any way for my subclassed DBI to know this?
> >
> >
> >Something like this might work:
> >
> > ... if exists &DBD::foo::db::selectrow_array;
> >
> >Also, take a look at the docs for the DBI's can() method. Though if you
> >want to rely on that you might want to look into the implementation to
> >check for edge cases or other subtle issues.
> >
> >
> >>b) is there an easy way to identify which other methods this could apply
> >>to
> >
> >
> >Nope. You'd have to use the above on all of them.
> >
> >Tim.
> >
> >
> >>Martin
> >>--
> >>Martin J. Evans
> >>Easysoft Ltd, UK
> >>http://www.easysoft.com
> >>
> >>
> >>On 29-Mar-2006 Tim Bunce wrote:
> >>
> >>>On Wed, Mar 29, 2006 at 11:54:32AM +0100, Martin J. Evans wrote:
> >>>
> >>>>The issue I am seeing is not quite as general as I made it sound. For
> >>>>selectrow_hashref I see prepare/execute/fetch/fetchrow_hashref (as I
> >>>>expect)
> >>>>but
> >>>>for selectrow_arrayref and selectrow_array I only see prepare.
> >>>
> >>>Generally... Drivers are free to implement any method in any way they
> >>>choose.
> >>>Their own methods don't have to call execute(), for example.
> >>>
> >>>Specifically... you're probably seeing the effect of the Driver.xst
> >>>C code that most compiled drivers embed into themselves. That code
> >>>embeds C implementations of selectall_arrayref and several other
> >>>methods into the driver itself. The selectall_arrayref code calls the
> >>>drivers C functions to do the work. The result is much, much, faster
> >>>than going though perl/DBI method dispatch for each row.
> >>>
> >>>Tim.
> >>>
> >>>
> >>>>Martin
> >>>>--
> >>>>Martin J. Evans
> >>>>Easysoft Ltd, UK
> >>>>http://www.easysoft.com
> >>>>
> >>>>
> >>>>On 29-Mar-2006 Martin J. Evans wrote:
> >>>>
> >>>>>Hi,
> >>>>>
> >>>>>I have subclassed DBI and override many methods including prepare,
> >>>>>execute
> >>>>>and
> >>>>>select* although they are predominantly just passed on to DBI.
> >>>>>
> >>>>>If I do:
> >>>>>
> >>>>>my $sth->prepare(sql);
> >>>>>$sth->execute;
> >>>>>
> >>>>>I see the prepare and execute and pass them on to DBI.
> >>>>>
> >>>>>If I do:
> >>>>>
> >>>>>$dbh->selectrow_array(sql);
> >>>>>
> >>>>>I see prepare and pass it on, but do not see execute. In my case this
> >>>>>is
> >>>>>more
> >>>>>than an annoyance as I cannot see any bound parameter passed to
> >>>>>execute.
> >>>>>
> >>>>>e.g.
> >>>>>
> >>>>>$selectrow_array = [
> >>>>> 'select b from mytest where a = ?',
> >>>>> undef,
> >>>>> \1
> >>>>> ];
> >>>>>prepare: select b from mytest where a = ?
> >>>>>!!! no execute here
> >>>>>
> >>>>>Or, perhaps I'm doing something wrong.
> >>>>>
> >>>>>Can anyone tell me if I should be seeing the execute when
> >>>>>$dbh->select***
> >>>>>is
> >>>>>called? I think I should.
> >>>>>
> >>>>>Thanks
> >>>>>
> >>>>>Martin
> >>>>>--
> >>>>>Martin J. Evans
> >>>>>Easysoft Ltd, UK
> >>>>>http://www.easysoft.com
> >
> >
> >
> >
>
