[wp-hackers] multiple calls to get_post_meta back to back as opposed to one call

[Haluk Karamete]

I assume that this caching is handled regardless of the
**define('ENABLE_CACHE',true);**.

What I'm curious though is how the caching is handled in this particular case?
Where does WP store the cached results for a get_post_meta?

In memory? As a file? in /cache folder as in define('ENABLE_CACHE',true);?

What's a good URL for learning more about this internal caching?

On Thu, Feb 7, 2013 at 1:55 PM, Haluk Karamete <halukkaramete at gmail.com> wrote:
> Very interesting. I would have never guessed that that would be the
> case. Smart!
>
>
>
> On Thu, Feb 7, 2013 at 1:43 PM, Andrew Nacin <wp at andrewnacin.com> wrote:
>> On Thu, Feb 7, 2013 at 4:30 PM, Haluk Karamete <halukkaramete at gmail.com>wrote:
>>
>>> This question can be formulated as
>>>
>>> Would it make sense ( from the mysql quiery point of view ) to build a
>>> functionality so that the following 2 liner code
>>>
>>> $fields = array('field_1','field_2',....'field_10');
>>> extract(get_post_metas($post->ID,$fields,true));
>>>
>>> will practically be speaking equal to something like
>>>
>>> $field_1 =  get_post_meta($post->ID,'field_1',true);
>>> $field_2 =  get_post_meta($post->ID,'field_2',true);
>>> ...
>>> $field_10 =  get_post_meta($post->ID,'field_10',true);
>>>
>>> First approach will be done with a single but slightly more
>>> complicated query whereas the latter will force 10 sql queries they
>>> tend to be simpler.
>>
>>
>> Test this and you will find that the latter is just one query, total. When
>> you call get_post_meta(), all meta for that post is queried and cached.
>>
>> Additionally, only the first argument to get_post_meta() is required. Call
>> it with just a post ID and you'll get back all metadata.
>>
>> Nacin
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