LINQtoCRM Wiki & Documentation Rss Feed

Updated Wiki: Home

friism — Sun, 23 May 2010 08:11:13 GMT

UPDATE Version 4.0.12 of the Microsoft CRM SDK includes a Linq query provider for CRM. I (friism) haven't tested it, but you should probably give it a try before going with LINQtoCRM. Read the short announcement.

Introduction

The Linq to CRM project provides a custom query provider for Microsoft Dynamics CRM/xRM (mscrm).

Found a query you think should work, but LinqtoCRM breaks or returns the wrong data? Please create a work-item or send it to me at friism+linqtocrm@gmail.com.

Features

Where-clauses of some complexity (And/Or, greater/less-than etc.)
Joins through relationtionships, including many-to-many ones
Translation of queries to FetchXML
Parsing of result to anonymous types or CRM entities
Orderby
Skip/Take
Count
Contains, StartsWith, EndsWith
CRMMetal tool for generating many-to-many relationship classes

Ressources

Todo

A visual debugger/visualizer to show were you've been too ambitious with your query. Bart De Smet seems to have the right idea
A "pedal-to-the-metal" toggle. If the code will be running with acess to the SQL-server, the developer can specify that the query should be translated to SQL and run on the filtered views at the flick of a switch.
The CRM web service is tangled up in the queryprovider code. It would be desirable if it could be moved outside and accessed though an interface. The code is rather dependent on the types exposed by the web service proxy-classes and it is not clear how this dependency could be removed without implementing something along the lines of SQLMetal/SPMetal.

Credits

Mel Gerats (implemented paging, contains and loads of other stuff)
Petteri Räty (rewrote query generation code, improved support for projections and conditions)
Michael Friis (initial version, various updates,maintenance)
Bart De Smet for the inspirational LINQtoSharePoint implementation
Michael Höhne for his FetchXML library
Matt Warren for his articles on QueryProvider-building: http://blogs.msdn.com/mattwar/archive/2007/08/03/linq-building-an-iqueryable-provider-part-v.aspx

Updated Wiki: Home

friism — Sun, 23 May 2010 07:09:47 GMT

UPDATE Version 4.0.12 of the Microsoft CRM SDK includes a Linq query provider for CRM. I (friism) haven't tested it, but you should probably give it a try before going with LINQtoCRM.

Introduction

Features

Where-clauses of some complexity (And/Or, greater/less-than etc.)
Joins through relationtionships, including many-to-many ones
Translation of queries to FetchXML
Parsing of result to anonymous types or CRM entities
Orderby
Skip/Take
Count
Contains, StartsWith, EndsWith
CRMMetal tool for generating many-to-many relationship classes

Ressources

Todo

A visual debugger/visualizer to show were you've been too ambitious with your query. Bart De Smet seems to have the right idea
A "pedal-to-the-metal" toggle. If the code will be running with acess to the SQL-server, the developer can specify that the query should be translated to SQL and run on the filtered views at the flick of a switch.
The CRM web service is tangled up in the queryprovider code. It would be desirable if it could be moved outside and accessed though an interface. The code is rather dependent on the types exposed by the web service proxy-classes and it is not clear how this dependency could be removed without implementing something along the lines of SQLMetal/SPMetal.

Credits

Mel Gerats (implemented paging, contains and loads of other stuff)
Petteri Räty (rewrote query generation code, improved support for projections and conditions)
Michael Friis (initial version, various updates,maintenance)
Bart De Smet for the inspirational LINQtoSharePoint implementation
Michael Höhne for his FetchXML library
Matt Warren for his articles on QueryProvider-building: http://blogs.msdn.com/mattwar/archive/2007/08/03/linq-building-an-iqueryable-provider-part-v.aspx

Updated Wiki: Home

friism — Sun, 01 Nov 2009 00:01:45 GMT

Introduction

Features

Where-clauses of some complexity (And/Or, greater/less-than etc.)
Joins through relationtionships, including many-to-many ones
Translation of queries to FetchXML
Parsing of result to anonymous types or CRM entities
Orderby
Skip/Take
Count
Contains, StartsWith, EndsWith
CRMMetal tool for generating many-to-many relationship classes

Ressources

Todo

A visual debugger/visualizer to show were you've been too ambitious with your query. Bart De Smet seems to have the right idea
A "pedal-to-the-metal" toggle. If the code will be running with acess to the SQL-server, the developer can specify that the query should be translated to SQL and run on the filtered views at the flick of a switch.
The CRM web service is tangled up in the queryprovider code. It would be desirable if it could be moved outside and accessed though an interface. The code is rather dependent on the types exposed by the web service proxy-classes and it is not clear how this dependency could be removed without implementing something along the lines of SQLMetal/SPMetal.

Credits

Mel Gerats (implemented paging, contains and loads of other stuff)
Petteri Räty (rewrote query generation code, improved support for projections and conditions)
Michael Friis (initial version, various updates,maintenance)
Bart De Smet for the inspirational LINQtoSharePoint implementation
Michael Höhne for his FetchXML library
Matt Warren for his articles on QueryProvider-building: http://blogs.msdn.com/mattwar/archive/2007/08/03/linq-building-an-iqueryable-provider-part-v.aspx

New Comment on "Updating CRM entities with LinqtoCRM"

friism — Fri, 03 Jul 2009 09:46:17 GMT

@decarufe: It's in th SDK http://msdn.microsoft.com/en-us/library/bb928994.aspx

New Comment on "Updating CRM entities with LinqtoCRM"

decarufe — Thu, 02 Jul 2009 18:36:01 GMT

How can I create a new entity?

Updated Wiki: Querying CRM with Linq

friism — Tue, 31 Mar 2009 19:27:58 GMT

Querying CRM with Linq

Webcasts

Samples

Setup:

    CrmService service = new CrmService();
    service.Url = "http://192.168.150.2:5555/mscrmservices/2007/crmservice.asmx";
    service.Credentials = 
        new NetworkCredential("administrator", "pass@word1", "litwareinc");
    service.CrmAuthenticationTokenValue = token;
 
	ICrmService s = new CrmWebService(service);
	CrmQueryProvider p = new CrmQueryProvider(s);

Retrieve CRM entity with all attributes:

            var res = from c in p.Linq<contact>()
                       select c;

Retrieve anonymous type:

            var res = from c in p.Linq<contact>()
                      select new { c.fullname };

Joins:

            var res = from c in p.Linq<contact>()
                      join a in p.Linq<account>()
                      on c.parentcustomerid.Value equals a.accountid.Value
                      select new { c.firstname, a.name };

Many-to-many join:

	var res = from u in p.Linq<systemuser>()
			  join sr in p.Linq<systemuserroles>() 
			  on u.systemuserid.Value equals sr.systemuserid.Value
			  join r in p.Linq<role>() 
			  on sr.roleid.Value equals r.roleid.Value
			  select new { u.fullname, r.name };

Contains:

            var res = from c in p.Linq<contact>()
                      where c.fullname.Contains("John")
                      select new { c.fullname };

Count:

            int res = (from c in p.Linq<contact>()
                       select c.contactid).Count();

Chained queries and paging. This query retrieves the first 100 contacts in batches of 10:

            var res = from c in p.Linq<contact>()
                      select new { c.fullname };
                       
            for (int i = 0; i < 10; i++)
            {
                var res2 = res.Skip(i*10).Take(10);
                foreach (var v in res2)
                    WriteLine(v.fullname);
            }

Distinct

            var res = (from c in p.Linq<contact>()
                      orderby c.firstname
                      select new {  c.firstname}
                      ).Distinct();

Updated Wiki: Home

friism — Mon, 16 Mar 2009 10:43:35 GMT

Introduction

The Linq to CRM project provides a custom query provider for Microsoft Dynamics CRM (mscrm).

Found a query you think should work, but LinqtoCRM breaks or returns the wrong data? Please create a work-item or send it to me at friism+linqtocrm@gmail.com.

Features

Where-clauses of some complexity (And/Or, greater/less-than etc.)
Joins through relationtionships, including many-to-many ones
Translation of queries to FetchXML
Parsing of result to anonymous types or CRM entities
Orderby
Skip/Take
Count
Contains, StartsWith, EndsWith
CRMMetal tool for generating many-to-many relationship classes

Ressources

Todo

A visual debugger/visualizer to show were you've been too ambitious with your query. Bart De Smet seems to have the right idea
A "pedal-to-the-metal" toggle. If the code will be running with acess to the SQL-server, the developer can specify that the query should be translated to SQL and run on the filtered views at the flick of a switch.
The CRM web service is tangled up in the queryprovider code. It would be desirable if it could be moved outside and accessed though an interface. The code is rather dependent on the types exposed by the web service proxy-classes and it is not clear how this dependency could be removed without implementing something along the lines of SQLMetal/SPMetal.

Credits

Mel Gerats (implemented paging, contains and loads of other stuff)
Petteri Räty (rewrote query generation code, improved support for projections and conditions)
Michael Friis (initial version, various updates,maintenance)
Bart De Smet for the inspirational LINQtoSharePoint implementation
Michael Höhne for his FetchXML library
Matt Warren for his articles on QueryProvider-building: http://blogs.msdn.com/mattwar/archive/2007/08/03/linq-building-an-iqueryable-provider-part-v.aspx

Updated Wiki: Change log

friism — Sat, 07 Mar 2009 20:08:56 GMT

Change log

7-03-2009: 0.3.3 Beta released

Bugfixes

16-01-2009: 0.3.2 Beta released

Bugfix

8-12-2008: 0.3.1 Beta released

Bugfix

6-12-2008: 0.3.0 Beta released

Significant query generator rewrite by Petteri Räty, many bugs squashed
CRMMetal tool for generating ManyToMany classes added by Michael Friis

22-8-2008: 0.2.7 Beta released

Bug fixes by Mel Gerats

3-6-2008: 0.2.6 Beta released.

Support for Distinct

25-5-2008: 0.2.5 Beta released. All new features are by Mel Gerats.

Unit tests
Support for paging using Skip/Take
Support for Contains, StartsWith and EndsWith
Support for Count
Support for chained queries
Support for selecting crm entities
Decoupling of LinqtoCRM and web service. LinqtoCRM can be compiled to a .dll and added to project

13-1-2008 : 0.2.4 Beta released.

Bug fixes
Unit test project (although no tests implemented)
The project is fairly usable and is now in beta

13-1-2008 : 0.2.3 Alpha released.

Bug fixes
Now compiles out of the box -- just change web reference and you're golden.
Minimal download with the files you need for your project
Demo video

07-1-2008 : 0.2.2 Alpha released.

Lots of smaller bug-fixes
Changed from WCF to old-school service reference

26-12-2007 : 0.2.1 Alpha released.

First new release in a while, sorry 'bout that!
Has been compiled with VS 2008 RTM and runs against CRM 4.0 RC0 (latest VPC)
Updates to result-processing code from Michael Höhne

06-08-2007 : 0.2.0 Alpha released.

Based on insights from Matt Warren's series of articles
Uses Visitor-pattern for query-generation
Ordering implemented
Ported to IQeryProvider/IQeryable-model

01-08-2007 : 0.1.1 Alpha released.

Compiles and runs (in it's own fashion) under VS 2008 Beta 2
FetchXML-library included as DLL in release (with thanks to Michael Höhne)

30-07-2007 : CodePlex site created, initial code uploaded (very crude early alpha - 0.1.0 Alpha)

Updated Wiki: Updating CRM entities with LinqtoCRM

friism — Sat, 07 Mar 2009 18:42:26 GMT

Updating CRM entities with LinqtoCRM

If you want to update entities queried with LinqtoCRM, you can't just retrieve entities with all attributes, change something and then update through the web service (a friend of mine worked out why this is so, but I've forgotten). Instead, you need to new up your own entitites and assign the relevant id (which is what CRM uses to determine which entity you're trying to change):

	var res = from c in p.Linq<contact>()
			  where c.fullname.StartsWith("Zwie")
                          // this is the important part
			  select new contact() { contactid = c.contactid };
 
	foreach (var con in res)
	{
		con.address1_line1 = "foo";
		service.Update(con);
		Console.WriteLine("updated " + con.contactid.Value);
	}

Updated Wiki: Updating CRM entities with LinqtoCRM

friism — Sat, 07 Mar 2009 18:41:56 GMT

Updating CRM entities with LinqtoCRM

 
	var res = from c in p.Linq<contact>()
			  where c.fullname.StartsWith("Zwie")
                          // this is the important part
			  select new contact() { contactid = c.contactid };
 
	foreach (var con in res)
	{
		con.address1_line1 = "foo";
		service.Update(con);
		Console.WriteLine("updated " + con.contactid.Value);
	}

Updated Wiki: Updating CRM entities with LinqtoCRM

friism — Sat, 07 Mar 2009 18:23:40 GMT

Updating CRM entities with LinqtoCRM

Updated Wiki: Updating CRM entities with LinqtoCRM

friism — Sat, 07 Mar 2009 18:23:21 GMT

!!Updating CRM entities with LinqtoCRM

Updated Wiki: Home

friism — Sat, 07 Mar 2009 18:22:53 GMT

Introduction

Features

Where-clauses of some complexity (And/Or, greater/less-than etc.)
Joins through relationtionships, including many-to-many ones
Translation of queries to FetchXML
Parsing of result to anonymous types or CRM entities
Orderby
Skip/Take
Count
Contains, StartsWith, EndsWith
CRMMetal tool for generating many-to-many relationship classes

Ressources

Todo

A visual debugger/visualizer to show were you've been too ambitious with your query. Bart De Smet seems to have the right idea
A "pedal-to-the-metal" toggle. If the code will be running with acess to the SQL-server, the developer can specify that the query should be translated to SQL and run on the filtered views at the flick of a switch.
The CRM web service is tangled up in the queryprovider code. It would be desirable if it could be moved outside and accessed though an interface. The code is rather dependent on the types exposed by the web service proxy-classes and it is not clear how this dependency could be removed without implementing something along the lines of SQLMetal/SPMetal.

Credits

Mel Gerats (implemented paging, contains and loads of other stuff)
Petteri Räty (rewrote query generation code, improved support for projections and conditions)
Bart De Smet for the inspirational LINQtoSharePoint implementation
Michael Höhne for his FetchXML library
Matt Warren for his articles on QueryProvider-building: http://blogs.msdn.com/mattwar/archive/2007/08/03/linq-building-an-iqueryable-provider-part-v.aspx

Updated Wiki: Home

friism — Sat, 07 Mar 2009 16:53:20 GMT

Introduction

Features

Where-clauses of some complexity (And/Or, greater/less-than etc.)
Joins through relationtionships, including many-to-many ones
Translation of queries to FetchXML
Parsing of result to anonymous types or CRM entities
Orderby
Skip/Take
Count
Contains, StartsWith, EndsWith
CRMMetal tool for generating many-to-many relationship classes

Ressources

Todo

A visual debugger/visualizer to show were you've been too ambitious with your query. Bart De Smet seems to have the right idea
A "pedal-to-the-metal" toggle. If the code will be running with acess to the SQL-server, the developer can specify that the query should be translated to SQL and run on the filtered views at the flick of a switch.
The CRM web service is tangled up in the queryprovider code. It would be desirable if it could be moved outside and accessed though an interface. The code is rather dependent on the types exposed by the web service proxy-classes and it is not clear how this dependency could be removed without implementing something along the lines of SQLMetal/SPMetal.

Credits

Mel Gerats (implemented paging, contains and loads of other stuff)
Petteri Räty (rewrote query generation code, improved support for projections and conditions)
Bart De Smet for the inspirational LINQtoSharePoint implementation
Michael Höhne for his FetchXML library
Matt Warren for his articles on QueryProvider-building: http://blogs.msdn.com/mattwar/archive/2007/08/03/linq-building-an-iqueryable-provider-part-v.aspx

Updated Wiki: Home

friism — Sat, 07 Mar 2009 13:44:36 GMT

Introduction

Features

Where-clauses of some complexity (And/Or, greater/less-than etc.)
Joins through relationtionships, including many-to-many ones
Translation of queries to FetchXML
Parsing of result to anonymous types or CRM entities
Orderby
Skip/Take
Count
Contains, StartsWith, EndsWith
CRMMetal tool for generating many-to-many relationship classes

Ressources

Todo

A visual debugger/visualizer to show were you've been too ambitious with your query. Bart De Smet seems to have the right idea
A "pedal-to-the-metal" toggle. If the code will be running with acess to the SQL-server, the developer can specify that the query should be translated to SQL and run on the filtered views at the flick of a switch.
The CRM web service is tangled up in the queryprovider code. It would be desirable if it could be moved outside and accessed though an interface. The code is rather dependent on the types exposed by the web service proxy-classes and it is not clear how this dependency could be removed without implementing something along the lines of SQLMetal/SPMetal.

Credits

Mel Gerats (implemented paging, contains and loads of other stuff)
Petteri Räty (rewrote query generation code, improved support for projections and conditions)
Bart De Smet for the inspirational LINQtoSharePoint implementation
Michael Höhne for his FetchXML library
Matt Warren for his articles on QueryProvider-building: http://blogs.msdn.com/mattwar/archive/2007/08/03/linq-building-an-iqueryable-provider-part-v.aspx

Updated Wiki: Home

friism — Sat, 07 Mar 2009 13:44:09 GMT

Introduction

Features

Where-clauses of some complexity (And/Or, greater/less-than etc.)
Joins through relationtionships, including many-to-many ones
Translation of queries to FetchXML
Parsing of result to anonymous types or CRM entities
Orderby
Skip/Take
Count
Contains, StartsWith, EndsWith
CRMMetal tool for generating many-to-many relationship classes

Ressources

Todo

A visual debugger/visualizer to show were you've been too ambitious with your query. Bart De Smet seems to have the right idea
A "pedal-to-the-metal" toggle. If the code will be running with acess to the SQL-server, the developer can specify that the query should be translated to SQL and run on the filtered views at the flick of a switch.
The CRM web service is tangled up in the queryprovider code. It would be desirable if it could be moved outside and accessed though an interface. The code is rather dependent on the types exposed by the web service proxy-classes and it is not clear how this dependency could be removed without implementing something along the lines of SQLMetal/SPMetal.

Credits

Mel Gerats (implemented paging, contains and loads of other stuff)
Petteri Räty (rewrote query generation code, improved support for projections and conditions)
Bart De Smet for the inspirational LINQtoSharePoint implementation
Michael Höhne for his FetchXML library
Matt Warren for his articles on QueryProvider-building: http://blogs.msdn.com/mattwar/archive/2007/08/03/linq-building-an-iqueryable-provider-part-v.aspx

Updated Wiki: Change log

friism — Sat, 07 Mar 2009 13:43:36 GMT

Change log

16-01-2009: 0.3.2 Beta released

Bugfix

8-12-2008: 0.3.1 Beta released

Bugfix

6-12-2008: 0.3.0 Beta released

Significant query generator rewrite by Petteri Räty, many bugs squashed
CRMMetal tool for generating ManyToMany classes added by Michael Friis

22-8-2008: 0.2.7 Beta released

Bug fixes by Mel Gerats

3-6-2008: 0.2.6 Beta released.

Support for Distinct

25-5-2008: 0.2.5 Beta released. All new features are by Mel Gerats.

Unit tests
Support for paging using Skip/Take
Support for Contains, StartsWith and EndsWith
Support for Count
Support for chained queries
Support for selecting crm entities
Decoupling of LinqtoCRM and web service. LinqtoCRM can be compiled to a .dll and added to project

13-1-2008 : 0.2.4 Beta released.

Bug fixes
Unit test project (although no tests implemented)
The project is fairly usable and is now in beta

13-1-2008 : 0.2.3 Alpha released.

Bug fixes
Now compiles out of the box -- just change web reference and you're golden.
Minimal download with the files you need for your project
Demo video

07-1-2008 : 0.2.2 Alpha released.

Lots of smaller bug-fixes
Changed from WCF to old-school service reference

26-12-2007 : 0.2.1 Alpha released.

First new release in a while, sorry 'bout that!
Has been compiled with VS 2008 RTM and runs against CRM 4.0 RC0 (latest VPC)
Updates to result-processing code from Michael Höhne

06-08-2007 : 0.2.0 Alpha released.

Based on insights from Matt Warren's series of articles
Uses Visitor-pattern for query-generation
Ordering implemented
Ported to IQeryProvider/IQeryable-model

01-08-2007 : 0.1.1 Alpha released.

Compiles and runs (in it's own fashion) under VS 2008 Beta 2
FetchXML-library included as DLL in release (with thanks to Michael Höhne)

30-07-2007 : CodePlex site created, initial code uploaded (very crude early alpha - 0.1.0 Alpha)

Updated Wiki: Change log

friism — Sat, 07 Mar 2009 13:43:20 GMT

Status

16-01-2009: 0.3.2 Beta released

Bugfix

8-12-2008: 0.3.1 Beta released

Bugfix

6-12-2008: 0.3.0 Beta released

Significant query generator rewrite by Petteri Räty, many bugs squashed
CRMMetal tool for generating ManyToMany classes added by Michael Friis

22-8-2008: 0.2.7 Beta released

Bug fixes by Mel Gerats

3-6-2008: 0.2.6 Beta released.

Support for Distinct

25-5-2008: 0.2.5 Beta released. All new features are by Mel Gerats.

Unit tests
Support for paging using Skip/Take
Support for Contains, StartsWith and EndsWith
Support for Count
Support for chained queries
Support for selecting crm entities
Decoupling of LinqtoCRM and web service. LinqtoCRM can be compiled to a .dll and added to project

13-1-2008 : 0.2.4 Beta released.

Bug fixes
Unit test project (although no tests implemented)
The project is fairly usable and is now in beta

13-1-2008 : 0.2.3 Alpha released.

Bug fixes
Now compiles out of the box -- just change web reference and you're golden.
Minimal download with the files you need for your project
Demo video

07-1-2008 : 0.2.2 Alpha released.

Lots of smaller bug-fixes
Changed from WCF to old-school service reference

26-12-2007 : 0.2.1 Alpha released.

First new release in a while, sorry 'bout that!
Has been compiled with VS 2008 RTM and runs against CRM 4.0 RC0 (latest VPC)
Updates to result-processing code from Michael Höhne

06-08-2007 : 0.2.0 Alpha released.

Based on insights from Matt Warren's series of articles
Uses Visitor-pattern for query-generation
Ordering implemented
Ported to IQeryProvider/IQeryable-model

01-08-2007 : 0.1.1 Alpha released.

Compiles and runs (in it's own fashion) under VS 2008 Beta 2
FetchXML-library included as DLL in release (with thanks to Michael Höhne)

30-07-2007 : CodePlex site created, initial code uploaded (very crude early alpha - 0.1.0 Alpha)

Updated Wiki: Home

friism — Sat, 07 Mar 2009 13:42:55 GMT

Introduction

Features

Where-clauses of some complexity (And/Or, greater/less-than etc.)
Joins through relationtionships, including many-to-many ones
Translation of queries to FetchXML
Parsing of result to anonymous types or CRM entities
Orderby
Skip/Take
Count
Contains, StartsWith, EndsWith
CRMMetal tool for generating many-to-many relationship classes

Ressources

*Querying CRM with Linq
*Getting started webcasthttp://friism.com/linqtocrm-030-released
*Querying relationships webcast
*Change log

Todo

A visual debugger/visualizer to show were you've been too ambitious with your query. Bart De Smet seems to have the right idea
A "pedal-to-the-metal" toggle. If the code will be running with acess to the SQL-server, the developer can specify that the query should be translated to SQL and run on the filtered views at the flick of a switch.
The CRM web service is tangled up in the queryprovider code. It would be desirable if it could be moved outside and accessed though an interface. The code is rather dependent on the types exposed by the web service proxy-classes and it is not clear how this dependency could be removed without implementing something along the lines of SQLMetal/SPMetal.

Credits

Mel Gerats (implemented paging, contains and loads of other stuff)
Petteri Räty (rewrote query generation code, improved support for projections and conditions)
Bart De Smet for the inspirational LINQtoSharePoint implementation
Michael Höhne for his FetchXML library
Matt Warren for his articles on QueryProvider-building: http://blogs.msdn.com/mattwar/archive/2007/08/03/linq-building-an-iqueryable-provider-part-v.aspx

Updated Wiki: Querying CRM with Linq

friism — Sat, 07 Mar 2009 13:32:13 GMT

Querying CRM with Linq

Webcasts

Samples

Setup:

    CrmService service = new CrmService();
    service.Url = "http://192.168.150.2:5555/mscrmservices/2007/crmservice.asmx";
    service.Credentials = 
        new NetworkCredential("administrator", "pass@word1", "litwareinc");
    service.CrmAuthenticationTokenValue = token;
 
	ICrmService s = new CrmWebService(service);
	CrmQueryProvider p = new CrmQueryProvider(s);

Retrieve CRM entity with all attributes:

            var res = from c in p.Linq<contact>()
                       select c;

Retrieve anonymous type:

            var res = from c in p.Linq<contact>()
                      select new { c.fullname };

Joins:

            var res = from c in p.Linq<contact>()
                      join a in p.Linq<account>()
                      on c.parentcustomerid.Value equals a.accountid.Value
                      select new { c.firstname, a.name };

Many-to-many join:

	var res = from u in p.Linq<systemuser>()
			  join sr in p.Linq<systemuserroles>() 
			  on u.systemuserid.Value equals sr.systemuserid.Value
			  join r in p.Linq<role>() 
			  on sr.roleid.Value equals r.roleid.Value
			  select new { u.fullname, r.name };

Contains:

            var res = from c in p.Linq<contact>()
                      where c.fullname.Contains("John")
                      select new { c.fullname };

Count:

            int res = (from c in p.Linq<contact>()
                       select c).Count();

Chained queries and paging. This query retrieves the first 100 contacts in batches of 10:

            var res = from c in p.Linq<contact>()
                      select new { c.fullname };
                       
            for (int i = 0; i < 10; i++)
            {
                var res2 = res.Skip(i*10).Take(10);
                foreach (var v in res2)
                    WriteLine(v.fullname);
            }

Distinct

            var res = (from c in p.Linq<contact>()
                      orderby c.firstname
                      select new {  c.firstname}
                      ).Distinct();