Using nHibernate version:1.2 trying to implement caching of frequently used Reference data for a Winforms app using syscache2. Is this possible? The previous postings on the forums and the help documentation is ambiguos. One gets the impression that collections cannot be cached.

NHibernate config is
configuration.SetProperty"hibernate.cache.provider_class", "NHibernate.Caches.SysCache2.SysCacheProvider, NHibernate.Caches.SysCache2");
configuration.SetProperty("hibernate.cache.use_second_level_cache", "true");
configuration.SetProperty("hibernate.cache.use_query_cache", "false");

Config file is as follows
<section name="syscache2" type="NHibernate.Caches.SysCache2.SysCacheSection, NHibernate.Caches.SysCache2"/>
</configSections>

<syscache2>
<cacheRegion name="PatientStatus">
<dependencies>
<tables>
<add name="price"
databaseEntryName="Paceart"
tableName="Paceart.Patient_Status" />
</tables>
</dependencies>
</cacheRegion>
</syscache2>
What should be the value of name in the "<tables><add name=" be ??

Mapping File is
<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" schema="paceart" default-lazy="false">
<class name="Paceart.Domain.Lookups.PatientStatus, Paceart.Domain" table="PATIENT_STATUS">
<cache usage="read-write" region="PatientStatus" />
<id name="Key" type="Guid" column="PatientStatusKey">
<generator class="assigned" />
</id>
<version name="Version" column="Version" type="Int32" unsaved-value="null" />
<property name="Code" column="Code" type="String" />
<property name="Description" column="Description" type="String" />
<property name="SortOrder" column="SortOrder" type="Int32" />
<property name="LongDescription" column="LongDescription" type="String" />
</class>
</hibernate-mapping>

The Select for the Patient Statuses shows up in the SQL Profiler everytime it is requested. Wanted to know if it is even possible to implement reference data caching using nHibernate. If yes what am I missing.

Thanks

Caching of queries has to be explicitly enabled with a call to SetCacheable() like this:



It is not dependent on the cache provider. Give that a try and let us know how it goes.

I do not want to cache the queries. I want to cache the actual collections/instances of objects.

I believe we are talking about the same thing... just different terminologies. Have a look at the second-last post of this thread to see if it helps you:

http://forum.hibernate.org/viewtopic.php?t=976960

How can I do this
session.CreateQuery("from Whatever").SetCacheable(true).List();
at the SessionFactory level as oppossed to the individual session level?

I don't believe it is possible to enable query caching by default for all queries... if that is what you meant. I am not too sure though. Maybe have a look at the API doc for ISessionFactory.

When I try to do what you suggested it infact added an extra select for each request. The first time I requested the list it selected it twice from the database. The same query shows up twice in the SQL profiler. On the second go around instead of grabbing the stuff from the cache(ideally) it gain fires the same select twice.

I just notice in your original post, you have

You need to set that to true as in

I was able to eliminate the extra select for each request of the collection. But still it goes to the database for the second request.
I have a very basic question, Is it even possible to cache collections in the second level cache?

Thanks

May be I am at the end of my helpfulness here... if I had even been helpful at all. Like many apps out there, my app have a lot of reference data (like a list of countries, for example). I have used the second level cache successfully with a method like this:



The cache provider I use is memcache. Maybe your problem is related to Syscache2? The final suggestion I have would be to isolate the problem; that is, maybe switch to a different cache provider to make sure your problem is not specific to Syscache2 and go from there.

Perhaps someone else could weight in here. Good luck.