[Catalyst] DB values that change very rarely

[Alexander Hartmaier]

On 2013-01-11 19:05, Francisco Obispo wrote:
> You really don't want this in DBIx::Class, you want fine grain control of when to fetch from the database, etc. Anyone can build their layer on top of DBIx::Class to implement caching.
>
> Using something like memcached would save you some database hits, you can either set the values to expire at a specified time / number of seconds, or you can set/delete keys as part of the procedures at insert/update/delete on the database.
>
> If you you Postgresql, you can actually take advantage of PgPool, which will give you the option to enable a caching layer… 
>
> Francisco
Please don't top post!
I *do* want this in DBIC so that a prefetch specified in some query
doesn't hit the database if the table is cached schema-wide. Any other
caching technique would mean changing every piece of code whereas this
would be transparent. I do know DBIx::Class quite well and don't think
that's possible with a component.
>
>
>
> On Jan 11, 2013, at 4:01 AM, Alexander Hartmaier <alexander.hartmaier at t-systems.at> wrote:
>
>> On 2013-01-10 16:15, Jesse Sheidlower wrote:
>>> In one of my apps, I have a number of tables that contain values that
>>> change very rarely. Think of something like a "category" table in an
>>> e-commerce app--they're mostly static, but every now and then you need
>>> to change or add or delete a category. These occasional changes do,
>>> however, need to be made by a (privileged) user, rather than a
>>> developer, so I can't just put them in the config file and edit this and
>>> restart the app when necessary. Since I don't know when they might
>>> change, I don't know how I could cache them, because when a change is
>>> made it needs to take effect immediately.
>>>
>>> These tables are used on almost every request. The result is that most
>>> of my controllers end up looking something like this, or having
>>> something like this at the end of them:
>>>
>>> sub add : Local {
>>>   my ( $self, $c ) = @_;
>>>
>>>   $c->stash->{title} = 'Add a new lemma';
>>>
>>>   $c->stash->{batches} = $c->model('WordsDB::Batch')->search();
>>>   $c->stash->{statuses} = $c->model('WordsDB::Status')->search();
>>>   $c->stash->{regions} = $c->model('WordsDB::Region')->search();
>>>   $c->stash->{subjects} = $c->model('WordsDB::Subject')->search();
>>>
>>>   $c->stash->{template} = 'add.tt';
>>> }
>>>
>>> This means that almost every page generation hits the database a whole bunch of
>>> unnecessary times, and that all of my controllers are cluttered.
>>>
>>> This must be a fairly common problem. What's the best way to deal with
>>> it--both the desire to persist what is mostly static data, and to keep
>>> my controllers clean?
>>>
>>> Thanks.
>>>
>>> Jesse Sheidlower
>>>
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>> I'd LOVE to see that functionality in DBIx::Class::Schema so prefetches
>> use the cached values to populate the related data instead of hitting
>> the database.
>>
>> --
>> Best regards, Alexander Hartmaier
>>
>>
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> Francisco Obispo 
> Director of Applications and Services - ISC
> email: fobispo at isc.org
> Phone: +1 650 423 1374 || INOC-DBA *3557* NOC
> PGP KeyID = B38DB1BE
>
>
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-- 
LG Alex