Euss - .NET Persistence Framework

New Post: Load XML data file partially

jmroyb — Fri, 18 Dec 2009 12:47:31 GMT

Hi,

I need to manage an XML data file of 1GB of size. But I can't load them in memory because I get a memory overflow exception. So I'm planing to load it using Evaluant.Uss.Xml.XmlProvider but I need to know if this provider can load it partially. The idea is read this file in several loops but load partially, apply some changes to this partial load and flush to file again.

Regards,

Josep Balague

New Post: Change Table at Load and Serialize without manipulating xml file

jmroyb — Fri, 11 Dec 2009 11:29:48 GMT

Hi,

I need to change the destination table at runtime in one Load and Serialize operation. Afterwards I must be the table mapped in the xml file.

How can I do this?

Cheers,

Josep Balague

New Post: Using SQL Server Stored Procedures

Tristan_Clow — Fri, 11 Dec 2009 10:05:16 GMT

NHibernate has the ability to use SQL Server stored procedures to fill, update, insert and delete records in the database.

Is Euss able to do the same thing?

I don't particularly want to get into the whole "stored procedures vs using tables directly" argument as we currently have a complete system currently running and are not looking to change it.

If anyone knows how to use stored procedures with Euss then that would be great.

New Post: Loading references

bjarte — Sat, 28 Nov 2009 15:53:55 GMT

I've made a class making it easy to bulk load references.

If you have a list of persons and want to ensure taht all persons addresses are loaded do it like this:

ReferenceLoader.LoadReference<Person>(persons, p=>p.Address)

Here's the code:

public static class ReferenceLoader
    {
        public static void LoadReference<T>(IEnumerable<T> objects, params string[] references)
        {
            List<IPersistableProxy> toHandle = new List<IPersistableProxy>();
            toHandle.AddRange((from o in objects where o is IPersistableProxy select o as IPersistableProxy));

            if (toHandle.Count > 0)
            {
                var oc = toHandle.ElementAt(0).ObjectContext;
                oc.PersistenceEngine.LoadReference((from item in toHandle select item.Entity), references);

                foreach (var item in toHandle)
                {
                    item.SetReferences();
                }
            }
        }

        public static void LoadReference<T>(IEnumerable<T> objects, params Expression<Func<T, object>>[] references)
        {
            List<string> referenceNames = new List<string>();

            foreach (var item in references)
                referenceNames.Add(GetMember(item).Member.Name);

            LoadReference<T>(objects, referenceNames.ToArray());
        }

        private static MemberExpression GetMember<M,T>(Expression<Func<M,T>> expression)
        {
            MemberExpression memberExpression = null;
            if (expression.Body.NodeType == ExpressionType.Convert)
            {
                var body = (UnaryExpression)expression.Body;
                memberExpression = body.Operand as MemberExpression;
            }
            else if (expression.Body.NodeType == ExpressionType.MemberAccess)
            {
                memberExpression = expression.Body as MemberExpression;
            }

            return memberExpression;
        }
    }

New Post: Example of a composition mapping

cristianrep — Fri, 20 Nov 2009 15:06:46 GMT

Sorry I pasted a wrong mapping file !

</Id>

</Entity>

</Id>

</Entity>

</Id>

</Entity>

</Id>

</Entity>

New Post: Example of a composition mapping

cristianrep — Fri, 20 Nov 2009 14:49:10 GMT

Hey Sebastien. Thanks for answering!

Here's the deal. A lot of legacy databases very poorly designed would map more than 1 entity per table. Now the funny part they don't have the same primary key so you end up with a lot of denormalization.

Looking at code I can trick it for the persisted ones using a mapping like the one bellow since you update info with WHERE CLAUSE Where name = ?:

</Id>

</Entity>

</Id>

</Entity>

</Id>

</Entity>

</Id>

</Entity>

Obviously the insert case would try to create two new records. So there I probably need to write something.

Since I got your attention, I tried to run the test cases and I got lot of errors. Do I do anything wrong or I run the wrong code?. Debugging just to get acquainted with code I fixed one for the case with Vehicles and Passengers. The problem occurs when the name of the foreign keys are not identical with primary keys names. Here's the mapping from your example:

</Id>

</Id>

</Reference>

</Entity>

I'm not sure how late initialization works. Looking at the code found an example for LazyLoadingOneToMany but what about plain domain classes?

Last, for synchronizing the foreign keys the framework emits an UPDATE clause after the insert of the record occurred, which is not going to work when foreign keys that cannot be NULL by column definition.

Regards,

cristian

New Post: Deprecated System.Data.OracleClient

sebastienros — Wed, 18 Nov 2009 16:10:38 GMT

In the <Driver/> section of the engine configuration, you have to specify Evaluant.Uss.SqlMapper.OracleDPDriver. It is explain at page 42 in the documentation.

New Post: .NET RIA Services

sebastienros — Wed, 18 Nov 2009 16:08:12 GMT

We currently don't handle .NET RIA Services. We have implemented ADO.NET Data Services for a while though. I think it's not so far from that, and we definitely will investigate more on this.

New Post: Example of a composition mapping

sebastienros — Wed, 18 Nov 2009 16:05:39 GMT

Should this one of these entities inherit from the other ?

New Post: .NET RIA Services

jmroyb — Mon, 16 Nov 2009 14:04:40 GMT

Hi again,

checked with NHibernate. Works fantastic:

http://blogs.msdn.com/brada/archive/2009/08/06/business-apps-example-for-silverlight-3-rtm-and-net-ria-services-july-update-part-nhibernate.aspx

Please can you confirm if EUSS works with .NET RIA Services ASAP?

Cheers.

Closed Issue: Incorrect syntax near 'nvarchar'. Must declare the scalar variable "@". [25275]

sebastienros — Mon, 16 Nov 2009 10:25:46 GMT

tried to use the inheritance mapping. I get an error for each when a try to create a new FACTORY. I use the example from documentation with the entity map looking like

<Entity type="Domain:Company" table="Company" discriminator-field="Type"
discriminator-value="Company">
<Id field="CompanyId">
<Generator name="guid" />
</Id>
<Attribute name="Name" field="Name" db-type="String"/>
<Attribute name="SiretNb" field="SiretNb" db-type="Int32"/>
</Entity>

<Entity type="Domain:Factory" table="Company"
discriminator-field="Type"
discriminator-value="Factory" >
<Id field="CompanyId">
<Generator name="guid" />
</Id>
<Attribute name="City" field=" City " db-type="String"/>
</Entity>

I checked the query which looks like:

INSERT INTO [Company] ([CompanyId] , [ City ] , [Name] , [SiretNb] ) VALUES ( @EntityId , @ City , @Name , @SiretNb )

The parameters inside look fine and have the correct values. It happens only when I try to save values for derived class. Tried the same thing for the company class and works fine.

Thank you Cristian

btw I like your work

New Post: .NET RIA Services

jmroyb — Mon, 16 Nov 2009 09:22:48 GMT

Hi,

.NET RIA Services uses entity framework for working but in its documentation is mentioning is possible use another DAL.

Have you test EUSS with RIA?

Cheers.

New Post: Deprecated System.Data.OracleClient

jmroyb — Mon, 16 Nov 2009 08:11:29 GMT

Hi,

Due Microsoft has deprecated System.Data.OracleClient, can we use ODT.NET from Oracle for Oracle connections? Is EUSS 100% compatible with ODT.NET from Oracle?

Please can you explain how to use this new provider?

Cheers.

New Post: Example of a composition mapping

cristianrep — Sat, 14 Nov 2009 22:22:21 GMT

Can you guys help me create a case where 2 entitites map and save in the same table and use a reference of composition type instead of an aggregate.

Thanks,

cristian

Commented Issue: Incorrect syntax near 'nvarchar'. Must declare the scalar variable "@". [25275]

cristianrep — Mon, 09 Nov 2009 18:35:34 GMT

Created Issue: Incorrect syntax near 'nvarchar'. Must declare the scalar variable "@". [25275]

cristianrep — Mon, 09 Nov 2009 18:04:01 GMT

tried to use the inheritance mapping. I get an error for each when a try to create a new FACTORY. I use the example from documentation with the entity map looking like

<Entity type="Domain:Company" table="Company" discriminator-field="Type"
discriminator-value="Company">
<Id field="CompanyId">
<Generator name="guid" />
</Id>
<Attribute name="Name" field="Name" db-type="String"/>
<Attribute name="SiretNb" field="SiretNb" db-type="Int32"/>
</Entity>

<Entity type="Domain:Factory" table="Company"
discriminator-field="Type"
discriminator-value="Factory" >
<Id field="CompanyId">
<Generator name="guid" />
</Id>
<Attribute name="City" field=" City " db-type="String"/>
</Entity>

I checked the query which looks like:

INSERT INTO [Factory] ([FactoryId] , [ City ] , [Name] , [SiretNb] ) VALUES ( @EntityId , @ City , @Name , @SiretNb )

The parameters inside look fine and have the correct values. It happens only when I try to save values for derived class. Tried the same thing for the company class and works fine.

Thank you Cristian

btw I like your work

New Post: Silverlight and Evaluant

sebastienros — Mon, 09 Nov 2009 13:53:23 GMT

Not on the client side, as we use for instance ANTLR which is not compatible. The only way is to do it on the server with web services.

New Post: Silverlight and Evaluant

jmroyb — Mon, 09 Nov 2009 13:51:22 GMT

Hi,

Did you test EUSS with Silverlight? Is it compatible?

Thanks,

Josep Balague

New Post: Ignoring attributes of enum and List types, incorrectly managed

neonp — Thu, 22 Oct 2009 10:10:06 GMT

Hi,

Issue 1 :

You should get the full type name of an entity you do create manually. so that you could have something like System.Collections.Generic.IList`1[[Evalos.Logica.Personal.Empleado]]. The type declared in metadata has to be the type you have in your model. In your case an IList<Evalos.Logica.Personal.Empleado>.

An attribute is a primitive type (string, int, double, byte, ...). A reference is a property which type is either a class of your model (the property then has to be virtual) or a IList<T> where T is a class of your model (the property does not need to be virtual, but needs to be an IList<>). If you do not want your reference to be known by euss, just have your property of type List<Evalos.Logica.Personal.Empleado> and do not specify anything in the metadata.

Regards,

Nicolas Penin

New Post: Ignoring attributes of enum and List types, incorrectly managed

jmroyb — Thu, 22 Oct 2009 08:07:11 GMT

Hi Nicolas,

Thanks for your quick answer.

Issue 1

PersonalSubordinado is a non mapped List attribute / reference as you wish say (I really cannot set where the difference is) based on a mapped type and within a mapped object called AnomaliaDestinatario. PersonalSubordinado is an object which must be instantiated but not filled by Load<AnomaliaDestinatario>(this is the reason of ignoring it). After reading short documentation about virtual properties, I have gone a step:

private IList<Empleado> _PersonalSubordinado = new List<Empleado>();

public virtual IList<Empleado> PersonalSubordinado

{

get { return _PersonalSubordinado; }

set { _PersonalSubordinado = value; }

}

IList<AnomaliaDestinatario> lstData;

lstData = oc.Context.Load<AnomaliaDestinatario>(typeof(AnomaliaDestinatario), “”);

meta.xml

? lstData[0].PersonalSubordinado.GetType().FullName

"Evaluant.Uss.ObjectContext.IPersistableCollection`1[[Evalos.Logica.Personal.Empleado, DigitekLogic, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]]"

? lstData[0].PersonalSubordinado.Count()

'lstData[0].PersonalSubordinado.Count()' produjo una excepción de tipo 'Evaluant.Uss.UniversalStorageException'

base {System.Exception}: {"The reference mapping PersonalSubordinado not found"}

What I really need in this issue is a list of AnomaliaDestinatario objects with a 0 length PersonalSubordinado list in every instance.

Issue 2

I never use int32 in scenarios where options can be multiple but I store an int32 value in data base. In my previous message when I use public Int32 ModoAgrupacion instead of public eACModoAgrupacionEnvio ModoAgrupacion I get a null exception in Load method. public Int32 ModoAgrupacion works fine, but not public eACModoAgrupacionEnvio ModoAgrupacion

Suggestions about documentation:

A dictionary of Evaluant concepts should be very useful
As Nhibernate has, short projects with examples should be very useful
Both your colleage Sebastien and yourself redirected me to read the documentation. Documentation is too much complex from other side :-)

Yours,

Josep Balague

Hi Nicolas,

Thanks for your quick answer.

Issue 1

PersonalSubordinado is a non mapped List attribute / reference as you wish say (I really cannot set where the difference is) based on a mapped type and within a mapped object called AnomaliaDestinatario. PersonalSubordinado is a transient object because it cannot be filled by Load<AnomaliaDestinatario>. After reading poor documentation about virtual properties, I have gone a step:

private IList<Empleado> _PersonalSubordinado = new List<Empleado>();

public virtual IList<Empleado> PersonalSubordinado

{

get { return _PersonalSubordinado; }

set { _PersonalSubordinado = value; }

}

IList<AnomaliaDestinatario> lstData;

lstData = oc.Context.Load<AnomaliaDestinatario>(typeof(AnomaliaDestinatario), “”);

meta.xml

? lstData[0].PersonalSubordinado.GetType().FullName

"Evaluant.Uss.ObjectContext.IPersistableCollection`1[[Evalos.Logica.Personal.Empleado, DigitekLogic, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]]"

? lstData[0].PersonalSubordinado.Count()

'lstData[0].PersonalSubordinado.Count()' produjo una excepción de tipo 'Evaluant.Uss.UniversalStorageException'

base {System.Exception}: {"The reference mapping PersonalSubordinado not found"}

What I really need in this issue is a list of AnomaliaDestinatario with a 0 length PersonalSubordinado list in every instance.

Issue 2

Suggestions about documentation:

· A dictionary of Evaluant concepts should be very useful

· As Nhibernate has, short projects with examples should be very useful

· Both your colleague Sebastien Ros and yourself redirected me to read documentation. In my opinion this is not an answer. Documentation is too much complex from other side J

Yours,

Josep Balague