Error using Linq for NHibernate

[DarkCamper]

Hi. I'm using dotConnect for PostgreSQL with NHibernate as explained in this post: http://forums.devart.com/viewtopic.php?f=3&t=28844.

I can open a session and execute a HQL query succesfully, but the same query using Linq throws this exception.

Code: Select all

"NHibernate.Exceptions.GenericADOException: could not execute query
[ select tenant0_.id as id0_, tenant0_.nombre as nombre0_, tenant0_.tenant_base as tenant3_0_ from core.tenant tenant0_ where tenant0_.id>:p0 ]
  Name:p1 - Value:1
[SQL: select tenant0_.id as id0_, tenant0_.nombre as nombre0_, tenant0_.tenant_base as tenant3_0_ from core.tenant tenant0_ where tenant0_.id>:p0] ---> Devart.Data.PostgreSql.PgSqlException: Parameter 'p0' is missing
   en Devart.Data.PostgreSql.PgSqlCommand.a(String A_0, Boolean A_1)
   en Devart.Data.PostgreSql.PgSqlCommand.InternalExecute(CommandBehavior behavior, IDisposable stmt, Int32 startRecord, Int32 maxRecords)
   en Devart.Common.DbCommandBase.InternalExecute(CommandBehavior behavior, IDisposable stmt, Int32 startRecord, Int32 maxRecords, Boolean nonQuery)
   en Devart.Common.DbCommandBase.ExecuteDbDataReader(CommandBehavior behavior, Boolean nonQuery)
   en Devart.Common.DbCommandBase.ExecuteDbDataReader(CommandBehavior behavior)
   en System.D
ata.Common.DbCommand.System.Data.IDbCommand.ExecuteReader()
   en NHibernate.AdoNet.AbstractBatcher.ExecuteReader(IDbCommand cmd)
   en NHibernate.Loader.Loader.GetResultSet(IDbCommand st, Boolean autoDiscoverTypes, Boolean callable, RowSelection selection, ISessionImplementor session)
   en NHibernate.Loader.Loader.DoQuery(ISessionImplementor session, QueryParameters queryParameters, Boolean returnProxies)
   en NHibernate.Loader.Loader.DoQueryAndInitializeNonLazyCollections(ISessionImplementor session, QueryParameters queryParameters, Boolean returnProxies)
   en NHibernate.Loader.Loader.DoList(ISessionImplementor session, QueryParameters queryParameters)
   --- Fin del seguimiento de la pila de la excepción interna ---
   en NHibernate.Loader.Loader.DoList(ISessionImplementor session, QueryParameters queryParameters)
   en NHibernate.Loader.Loader.ListIgnoreQueryCache(ISessionImplementor session, QueryParameters queryParameters)
   en NHibernate.Loader.Loader.List(ISessionImplemen
tor session, QueryParameters queryParameters, ISet`1 querySpaces, IType[] resultTypes)
   en NHibernate.Hql.Ast.ANTLR.Loader.QueryLoader.List(ISessionImplementor session, QueryParameters queryParameters)
   en NHibernate.Hql.Ast.ANTLR.QueryTranslatorImpl.List(ISessionImplementor session, QueryParameters queryParameters)
   en NHibernate.Engine.Query.HQLQueryPlan.PerformList(QueryParameters queryParameters, ISessionImplementor session, IList results)
   en NHibernate.Impl.SessionImpl.List(IQueryExpression queryExpression, QueryParameters queryParameters, IList results)
   en NHibernate.Impl.AbstractSessionImpl.List(IQueryExpression queryExpression, QueryParameters parameters)
   en NHibernate.Impl.ExpressionQueryImpl.List()
   en NHibernate.Linq.DefaultQueryProvider.ExecuteQuery(NhLinqExpression nhLinqExpression, IQuery query, NhLinqExpression nhQuery)
   en NHibernate.Linq.DefaultQueryProvider.Execute(Expression expression)
   en NHibernate.Linq.DefaultQueryProvider.Execute[TResult](
Expression expression)
   en Remotion.Linq.QueryableBase`1.GetEnumerator()
   en System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)
   en System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source)
   en ErrorDevartPotgreSQL.Form1.Form1_Load(Object sender, EventArgs e) en o:\\Pruebas\\ErrorDevartPotgreSQL\\ErrorDevartPotgreSQL\\Form1.cs:línea 56"

And this is the code i've tested

Code: Select all

Configuration cfg = new Configuration().AddAssembly(typeof(Program).Assembly);
ISessionFactory sessionFactory = cfg.BuildSessionFactory(); 
ISession session = sessionFactory.OpenSession();

//This works
var query = session.CreateQuery("from Tenant where Id > 1");
var res = query.List();

//This throws the exception
var query2 = session.Query<ErrorDevartPotgreSQL.Tenant>().Where(x => x.Id > 1);
var res2 = query2.ToList();

I've tried with NH versions 3.3.4 and 4.0.1 to the same effect. DotConnect version is 7.3.352.0 and PostgreSql is 9.4.

Do you have any idea about what could be wrong?

Thanks!

[MariiaI]

We couldn't reproduce this error in our environment. Please send us a small test project with the necessary DDL/DML scripts, with which this issue could be reproduced. This will significantly speed up the process of determining the cause of this issue.

[DarkCamper]

Hi, have you been able to replicate the problem using the small project I sent you?

If you need more information or something just ask for it, I'll gladly help you.

Thanks.

[MariiaI]

Sorry for the delay. Your letter was blocked by our mail filter for some reason. We have reproduced the issue with your sample project. This behaviour is related to NHibernate, not dotConnect for PostgreSQL. To avoid the error, please open the DevartDriver.cs file and replace this code:

Code: Select all

 public override string NamedPrefix
        {
            get { return ":"; }
        }

with this

Code: Select all

 public override string NamedPrefix
        {
            get { return "@"; }
        }

Please tell us if this helps.

[DarkCamper]

It works! Thanks a lot for your help