DevForce 2010: Cache is bypassed

Cache is bypassed

Printed From: IdeaBlade
Category: DevForce
Forum Name: DevForce 2010
Forum Discription: For .NET 4.0
URL: http://www.ideablade.com/forum/forum_posts.asp?TID=2954
Printed Date: 18-Apr-2025 at 2:06am

Topic: Cache is bypassed

Posted By: Frederic
Subject: Cache is bypassed
Date Posted: 09-Sep-2011 at 12:51pm

Good afternoon,

Before posting, I had a quick look to see if the question was already adressed but could not find the answer, still, I apologize if the issue was already discussed.

I'm using Devforce 2010 version 6.0.9.0 on SQL Server 2008 R2.

It seems that an EntityQuery is not using entities in the cache (but it uses the ones in the datastore) whenever a condition is made using a navigation property.

For instance, if I have an entity called Band and another called Member with members belonging to one band (one to many relationship), the following query:

Int32 membersCount = manager.GetQuery<Member>().Where(e => e.Band.Name == "U2").AsEnumerable<Member>().Count();

membersCount will show 3

Now add a new bass player to the band using:

Member newBassPlayer = new Member();

newBassPlayer.Name = " http://en.wikipedia.org/wiki/Adam_Clayton - Adam Clayton ";

newBassPlayer.Band = manager.GetQuery<Band>().Where(e => e.Name == "U2").First<Band>();

manager.AddEntity(newBassPlayer);

For now the new player is added to the cache and is not yet stored in the database.

Now, the member count still shows 3 and using SQL server profiler, I notice that the query is performed on the datastore instead of the cache as expected by using "AsEnumerable<Member>".

Int32 membersCount = manager.GetQuery<Member>().Where(e => e.Band.Name == "U2").AsEnumerable<Member>().Count();

What is the best practise to force the query to be performed on the cache and not on the datastore?
It seems that previous versions of Devforce could specify to include records from Navigation properties (using the Include method) but I seem not able to do that anymore?
Can you point me to relevant documentation regarding the proper use of the cache or other best practices?

Thanks a lot for your support

Frederic

Replies:

Posted By: sbelini
Date Posted: 12-Sep-2011 at 5:26pm

Hi Frederic,

I was not able to reproduce the issue here. The count value changed and the datasource was not hit the second time when executing the same query.

Here's my test (against NorthwindIB):

var mgr = new NorthwindIBEntities();

// Will hit datasource

var ordersCount = mgr.GetQuery<Order>().Where(ord => ord.Employee.FirstName == "Nancy Lynn").AsEnumerable<Order>().Count();

var newOrder = new Order();

newOrder.OrderDate = DateTime.Today;

newOrder.Employee = mgr.GetQuery<Employee>().Where(emp => emp.FirstName == "Nancy Lynn").First<Employee>();

mgr.AddEntity(newOrder);

// Will not hit datasource

var ordersCount2 = mgr.GetQuery<Order>().Where(ord => ord.Employee.FirstName == "Nancy Lynn").AsEnumerable<Order>().Count();

Have you by any chance modified DefaultQueryStrategy? (i.e. mgr.DefaultQueryStrategy)

Could you provide a simple solution reproducing the issue? (preferably against NorthwindIB)

Also, you will find interesting these articles from DevForce Resource Center:

http://drc.ideablade.com/xwiki/bin/view/Documentation/query-strategy - Control query execution

http://drc.ideablade.com/xwiki/bin/view/Documentation/query-fetchstrategy - Control where the query executes

Regards,

Silvio.

Posted By: Frederic
Date Posted: 13-Sep-2011 at 12:42pm

Thanks a lot Silvio to provide time to assist me,

Actually I did not mention the fact that in my sample I made a derivation of entity to produce the problem. At first, I thought it was not important to mention but I must be wrong.

I made changes to the model so that to get a derived entity as shown in the picture at the end of this post.

Anyway, this is the sample I have been using:

static void Main(string[] args)

{

NorthwindIBEntities manager = new NorthwindIBEntities(

shouldConnect: true,

dataSourceExtension: String.Empty,

entityServiceOption: IbEm.EntityServiceOption.UseLocalService,

compositionContextName: String.Empty);

IbEm.EntityQuery<Employee> employees = manager.GetQuery<Employee>();

IbEm.EntityQuery<Group> groups = manager.GetQuery<Group>();

Group u2 = groups.Where<Group>(gr => gr.Name == "U2").First<Group>();

employees = employees.Where(e => e.Group.Name == "U2") as IbEm.EntityQuery<Employee>;

Int32 employeeCount = employees.AsEnumerable<Employee>().Count();

Employee newEmployee = new Employee();

newEmployee.EmployeeID = 11;

newEmployee.LastName = "Hewson";

newEmployee.FirstName = "Paul David";

newEmployee.Title = "Sales Representative";

newEmployee.TitleOfCourtesy = "Mr.";

newEmployee.BirthDate = new DateTime(1960, 5, 10);

newEmployee.HireDate = new DateTime(2011, 9, 7);

newEmployee.Address = "Sunset Boulevard";

newEmployee.City = "Hollywood";

newEmployee.Region = "CA";

newEmployee.PostalCode = "22222";

newEmployee.Country = "USA";

newEmployee.HomePhone = "(222) 222-2222";

newEmployee.Extension = "222";

newEmployee.Notes = "Former singer of U2";

newEmployee.PhotoPath = "http://en.wikipedia.org/wiki/File:Bono_at_the_2009_Tribeca_Film_Festival.jpg";

newEmployee.ReportsToEmployeeID = 2;

newEmployee.RowVersion = 0;

newEmployee.Group = u2;

manager.AddEntity(newEmployee);

Int32 newEmployeeCount = employees.AsEnumerable<Employee>().Count();

}

I can provide you with the exact code sample + the mdf file in the next post.

As a final note these are the modifications I made to the NorthwindIB model:

Thanks again for your dedication and time.

Frederic

Posted By: sbelini
Date Posted: 13-Sep-2011 at 12:44pm

Thanks for the update, Frederic.

I'll test it here and follow up.

Silvio.

Posted By: Frederic
Date Posted: 13-Sep-2011 at 1:10pm

Hi Silvio,

as mentionned, here are the sample files:

uploads/1263/TestCount.zip - uploads/1263/TestCount.zip

Frederic

Posted By: sbelini
Date Posted: 15-Sep-2011 at 12:36pm

Hi Frederic,

I have tested and verified the issue in DevForce 6.0.9.

Also, I checked and this issue is no longer present in the latest version of DevForce (6.1.2)

Upgrading will resolve the problem.

Kind regards,

Silvio.

Posted By: Frederic
Date Posted: 16-Sep-2011 at 8:14am

Hi Silvio,

This morning, I did the upgrade to version 6.1.2 of Devforce and you are right my problem has gone away both in my small sample application I sent you the other day as well as my main application.

I would consider the case closed. A thumbs up to you.

Good job, thanks

Frederic