disabling cache

[atomly]

Is it possible to completely turn off the cache in Activate?

I tried adding the following to my context:

  override def liveCacheType = CacheType.weakReferences

  protected lazy val noCache = CustomCache[Entity](

    cacheType = CacheType.softReferences,

    limitOption = Some(0)

  )

  override def customCaches = List(noCache)

But I'm still seeing some caching behavior.

I need to completely turn it off for this app because I am interfacing with a legacy database that is still being written to by another (rails) app as well.

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[Flavio W. Brasil]

Hi,

Activate must guarantee that there is only one instance in memory for each entity in the database. Without this guarantee it isn’t possible to ensure many properties that Activate delivers as features. The implication is that if the entity isn’t collected by the GC, it will be shared by different transactions.

Anyway, I think you are trying to use the wrong mechanism. Even if the caching behavior was the one you were expecting, it wouldn’t be capable to ensure consistency. It is possible to recover an entity, do some processing and meanwhile the entity can be modified by the rails app.

The solution for this is the optimistic offline locking. Using it, it is even possible to keep the cache without limits.

Cheers,

-- 

Flavio W. Brasil

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[atomly]

but in order to do that, don't I have to add the version column to my tables? and doesn't rails have to write to it?

atomly

[Flavio W. Brasil]

Does the application using Activate perform writes? If not, there is a mechanism to use the update_at field.

If yes, is it possible to create the version column and keep it updated using a trigger? Or even use a view that translates updated_at to version?

Cheers,

-- 

Flavio W. Brasil

[atomly]

yes, unfortunately, both sides write... I could try the trigger-- I would then need to do this for every table, right?

the other problem, though, is that I'm seeing stale data-- if I turn on locking for reads and as the trigger, will this be alleviated?

atomly

[Flavio W. Brasil]

Yes, the optimistic offline locking provides full consistency.

Cheers,

-- 

Flavio W. Brasil

[andrewjam...@gmail.com]

But is it possible to disable caching in activate?