[Dbix-class] Fastest method to check for key existence?

[Dmitry L.]

On 12 February 2015 at 14:27, Hartmaier Alexander
<alexander.hartmaier at t-systems.at> wrote:
> I'd additinally restrict the columns returned to the pk columns to save
> bytes going over the wire and using HRI to not instantiate a result object.
>
> Looks like a nice addition to DBIC::Helpers!
>
Looks like already there: DBIx::Class::Helper::ResultSet::Shortcut::HasRows


>
> On 2015-02-12 08:22, QE :: Felix Ostmann wrote:
>
> We are using this function in our ResultSet.pm:
>
> sub exists {
>     my ($self, $query) = @_;
>
>     return $self->search($query, { rows => 1, select => [\1] })->single;
> }
>
>
> Have a nice day
> Felix
>
>
> 2015-02-12 1:05 GMT+01:00 Charlie Garrison <garrison at zeta.org.au>:
>>
>> Good morning,
>>
>> On 11/2/15 at 10:58 PM +0100, Ekki Plicht (DF4OR) <ekki at plicht.de> wrote:
>>
>> >I am thinking of setting up a special resultset which contains only
>> >the key as a returned value by SELECT, but I am wondering if there is
>> >a faster method.
>>
>> Put a method in your ResultSet class, eg:
>>
>> sub key_exists {
>>     my ($self, $key) = @_;
>>     my $row = $self->find( $key );
>>     return $row ? 1 : 0;
>> }
>>
>>
>> Elsewhere:
>>
>> my $got_row = $schema->resultset('RSClass')->key_exists($key);
>>
>>
>> Charlie
>>
>> --
>>    Charlie Garrison  <garrison at zeta.org.au>
>>    github.com/cngarrison   metacpan.org/author/CNG
>>
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>>
>>
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>
>
>
>
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-- 
//wbr, Dmitry L.