两个键可以指向memcache中的相同数据

Question

I am using PHP and Memcache. I want multiple keys to point to the same data.

$datawallright = $memcache->get('wads'.$wall->getIdwall());

This is how I retrieve the data. If there is no data I make some MySql queries, which take time. Most of the times the key points to unique data. The problem is that sometimes I want more keys to point to the same data.

$memcache->set('wads'.$wall->getIdwall(), $datawallright, false, 3600) or die ("Failed to save data at the server");

If I do this it is going to save the data in memcache which is ok for the unique values, but it is going to store the data multiple times in the other scenario, which is a waste of space in the cache.

So what I want bassicaly is wads1 and wads2 to point to the same data in memcache.

Answer 1

No, there is no native way to make memcached share objects between keys.

If you really need to implement such a thing, you could however implement such a workaround yourself. For example, assume that key hello maps to object world.

You could make it so that in your codebase, any key that has for value {'alias': N} will make your code perform a memcached lookup for key N. So in this case, you would just store data as follow:

hello -> world

hello2 -> {'alias': 'hello'}

hello3 -> {'alias': 'hello'}

This is likely a bad pattern to have in your code though; it would be cleaner and easier to maintain if you just always refer to the key that points to the data you want in the first place (and it would save an extra memcached hit every time).