Hi All,

Just a quick question. I am using the SysCacheProvider with Query Caching turned on. This is for an ASP.Net app. If 2 or more requests come in with the same query (Press F5 a couple of times) then I get this exception (From NHibernate Logs).

2006-07-07 11:05:28,888 INFO NHibernate.Loader.Loader - [VERY LONG QUERY]
2006-07-07 11:05:28,888 INFO NHibernate.Loader.Loader - [VERY LONG QUERY]
2006-07-07 11:05:28,888 INFO NHibernate.Loader.Loader - [VERY LONG QUERY]
2006-07-07 11:05:28,888 INFO NHibernate.Loader.Loader - [VERY LONG QUERY]
2006-07-07 11:05:28,904 WARN NHibernate.Util.ADOExceptionReporter - System.ArgumentException: Item has already been added. Key in dictionary: "NHibernate-Cache:NHibernate.Cache.StandardQueryCache:sql: [VERY LONG QUERY]
at System.Collections.Hashtable.Insert(Object key, Object nvalue, Boolean add)
at System.Collections.Hashtable.Add(Object key, Object value)
at NHibernate.Caches.SysCache.SysCache.Put(Object key, Object value)
at NHibernate.Cache.StandardQueryCache.Put(QueryKey key, IType[] returnTypes, IList result, ISessionImplementor session)
at NHibernate.Loader.Loader.List(ISessionImplementor session, QueryParameters queryParameters, ISet querySpaces, IType[] resultTypes)
at NHibernate.Loader.CriteriaLoader.List(ISessionImplementor session)
at NHibernate.Impl.SessionImpl.Find(CriteriaImpl criteria)
2006-07-07 11:05:28,904 INFO NHibernate.Loader.Loader - [VERY LONG QUERY]
2006-07-07 11:05:28,904 ERROR NHibernate.Util.ADOExceptionReporter - Item has already been added. Key in dictionary: "NHibernate-Cache:NHibernate.Cache.StandardQueryCache:sql: [VERY LONG QUERY]


Is there any information available on this? Is this a bug? Is Query Caching stable? Do I have to implement my own locking on top of
NHibernate (if using cache)? That seems like an inefficient solution.

Cheers

Guido Tapia

Hibernate version: 1.0.2
Name and version of the database you are using:SQL Server 2000

Hi,

I have also seen this error occasionally and am not sure if there is an issue with the Cache provider (unlikely) or something that I am doing wrong (very likely).

Any tips on how to track down the cause of this error or any best practices for using the SysCache?

Thanks,

Jason

Do you get the same error with other caches?

Thanks k-dub...I notice that Sergey has responded in another thread to say that this will be fixed in 1.0.3. I haven't tried with the other caches and will wait to try out 1.0.3 first.

Cheers,

Jason