Microsoft Sync Framework : Sync Services for ADO.NET

Sync Framework 2.0 Available for Download

LarenC — Mon, 19 Oct 2009 15:27:00 GMT

I am happy to announce the availability of Sync Framework 2.0. Sync Framework 2.0 expands on the capabilities offered by Sync Framework 1.0:

Adds features that cater to new scenarios or scenarios that were difficult to support.
Reduces the amount of work required to develop providers.
Supports more data sources with new built-in providers.

The major new features and improvements included in Sync Framework 2.0 are:

In Core Components:

Simple Providers: Reduce the amount of work required to develop providers, especially when the data source has very few synchronization-related capabilities, such as change-tracking. The goal is to enable a developer to write a provider without having to become a synchronization expert. The majority of the code that is required for a simple provider is limited to that responsible for interacting with the data source. Simple providers support many complex synchronization scenarios, such as filtering, concurrency and constraint conflict handling, and anchor-based enumeration.
Flexible Filtering: Change unit filters and custom filters have been added to the custom provider components. These filters, in addition to the item filters from Sync Framework 1.0, enable you to filter your data in whatever way is most useful. Filter negotiation allows the source and destination providers to negotiate the filter used during the synchronization session. Change unit filters enable a provider to specify that, while the replica it serves stores all items in the synchronization scope, the replica stores a reduced representation of each item. For example, when an item is a contact a device might store only the name and phone number of the contact as compared to the complete contact stored on a PC. Custom filters enable you to define a filter in whatever way is most appropriate, including filters that allow an item to move into or out of the filter as the item data changes. For example, a media storage device stores only songs that are rated as three stars or better. When the rating on a song changes from four stars to two stars, the song moves out of the filter. Filter negotiation allows a destination provider to specify the filter to be used by the source provider during change enumeration; the source provider can accept or reject a filter. If a source provider does not support the requested filter then the destination provider can choose to receive all of the data and do the filtering itself.
Improved Conflict Handling: Additional conflict scenarios are supported, such as reporting constraint conflicts, managing logged conflicts, and resolving conflicts by using a last-writer-wins policy. Constraint conflicts are conflicts that violate constraints that are put on items or change units, such as the relationship of folders or the location of identically named data within a file system. Sync Framework includes components to help resolve constraint conflicts and apply the resolution to the destination replica. Conflict logging is enhanced by Sync Framework components that help manage the log, such as by removing obsolete conflicts. A last-writer-wins conflict resolution policy can be used to resolve concurrency conflicts (in which an item is updated by more than one replica) by keeping the most recently made change, regardless of where the change was made. Sync Framework supports this policy by enabling an application to retrieve the time a change was made on the source and destination replicas. The application can then compare the two times and apply the last change.
Data Conversion between Providers: In some scenarios, synchronization providers synchronize the same type of data (such as sales data), but the data format that each provider requires is different. To address this scenario, Sync Framework enables you to implement interfaces that convert data to the format that each provider requires. In addition to data conversion APIs that can be used for any type of custom provider, Sync Framework also includes conversion APIs specifically for the file synchronization provider.
Change Application Service: Increases the flexibility and usefulness of the change applier component of Sync Framework. By performing the same actions as the standard change applier, but in a more granular way, the change application service gives a destination provider the ability to use only the features that it requires.
Tracing: Enables you to trace the execution of several components, which is useful during application debugging. This download provides the .tmf files that can be used to view a trace, flush the logger, and format the binary trace file. For more information about how to trace Sync Framework execution, see “Tracing Sync Framework Components” in the documentation that installs with the Sync Framework SDK.

In Database Providers:

New Database Providers (SQL Server and SQL Server Compact): Enable hub-and-spoke and peer-to-peer synchronization for SQL Server, SQL Server Express, and SQL Server Compact. Sync Framework automatically creates all of the commands that are required to communicate with each database. You do not have to write synchronization queries as you do with other providers. The providers support: flexible initialization options; batching of changes based on data size; and maintenance tasks, such as metadata cleanup and server database restore.
Robust Memory-Based Batching: Previous versions of Sync Framework and Sync Services for ADO.NET provided a way for developers to define their own batching logic but there were a lot of limitations, including significant complexity, excessive chattiness, out of memory issues, and restrictions on usage. Sync Framework 2.0 addresses all of these issues by providing a more complete and robust batching API. Developers no longer have to write batching logic themselves because Sync Framework divides changes into batches based on several properties in the API. Batches are now defined by memory consumption rather than the number of rows synchronized, which has eliminated out-of-memory issues for most common scenarios.
Provisioning and Management APIs: Provisioning and initialization activities that were previously exposed only through Visual Studio tooling have now been added to the database provider APIs. This includes the ability to provision an existing database by adding the change-tracking tables and triggers that are required by Sync Framework. It also includes the ability to start with an empty database, create the user schema, and provision that schema based on another server or client database that has already been provisioned.
Performance Improvements: The new database providers in this release have been thoroughly tested in large-scale scenarios in which a single server supports thousands of clients with hundreds of concurrent synchronization operations. This testing resulted in a large number of internal performance improvements that enable Sync Framework database providers to perform as well as other Microsoft technologies like Remote Data Access (RDA) while offering a wide range of capabilities that compete with end-to-end solutions like merge replication.

In File Synchronization Provider:

· Data Conversion between Providers: The data transfer interface used by the file synchronization provider is now available in managed code. A custom provider that synchronizes some other data type can use the data transfer interface to convert its data to synchronize with a file synchronization provider.

· Better File Transfer Performance: Improvements to the way file data is copied allow file data to be transferred up to 30% faster than in Sync Framework 1.0.

· More Robust Synchronization: Instead of failing the entire synchronization session when a single file cannot be synchronized (including failures caused by network issues), the failure is flagged and the synchronization session continues.

To learn more about Sync Framework or to download Sync Framework 2.0, please visit the Sync Framework Developer Center.

Announcing Sync Framework 2.0 CTP2

liamca — Fri, 05 Jun 2009 01:49:00 GMT

I am extremely happy to announce the availability of Sync Framework 2.0 CTP2 . Sync Framework 2.0 expands on the capabilities offered by Sync Framework 1.0:

Adds features that cater to new scenarios or scenarios that were difficult to support.
Reduces the amount of work required to develop providers.
Supports more data sources with new built-in providers.

The major new features included in this CTP are:

New database providers (SqlSyncProvider and SqlCeSyncProvider)
Enable hub-and-spoke and peer-to-peer synchronization for SQL Server, SQL Server Express, and SQL Server Compact. Sync Framework automatically creates all of the commands that are required to communicate with each database. You do not have to write synchronization queries as you do with other providers. The providers support: flexible initialization options; batching of changes based on data size; and maintenance tasks, such as metadata cleanup and server database restore.
Custom filters
Enable a filtered replica to store item data only for items that are in the filter, such as a media storage replica that stores only songs that are rated as three stars or better. As the rating on a song changes, an item might move in or out of the filter. A filter-tracking replica is another replica in the community that can identify which items are in the filter and which have moved in or out of the filter recently. A filter-tracking replica may store item data for items that are not in the filter. Sync Framework supports efficient synchronization between filtered replicas and filter-tracking replicas, and maintains all of the necessary metadata.
Improved conflict handling
Sync Framework added several features in this release that make it easier to handle conflicts.

Constraint conflict handling: Sync Framework now supports constraint conflicts, which are conflicts that violate constraints that are put on items or change units, such as the relationship of folders or the location of identically named data within a file system. A destination provider can report a constraint conflict to Sync Framework, and use Sync Framework components to resolve the conflict and determine how to apply the resolution to the destination replica.
Conflict logging: Sync Framework defines a set of conflict log interfaces and provides components that help manage conflicts in the log. Sync Framework also provides an in-memory implementation of the conflict log interfaces for replicas that do not contain a conflict log. It can be useful to save conflicts in a log so that they can be processed separately from the synchronization session, such as when a user needs to review conflicts and decide how to resolve them.
Last-writer-wins conflict resolution: An application might want to resolve concurrency conflicts (in which an item is updated by more than one replica) by keeping the most recently made change, regardless of where the change was made. Sync Framework supports this resolution option by enabling an application to retrieve the time a change was made on the source and destination replicas. The application can then compare the two times and apply the last change.
Improved simple provider conflict handling: Simple providers include a new set of conflict handling interfaces that make it easier to specify resolution actions for concurrency and constraint conflicts.

Data conversion between providers
In some scenarios, synchronization providers synchronize the same type of data (such as sales data), but the data format that each provider requires is different. To address this scenario, Sync Framework enables you to implement interfaces that convert data to the format that each provider requires. In addition to data conversion APIs that can be used for any type of custom provider, Sync Framework also includes conversion APIs specifically for the file synchronization provider.
Change application service
Sync Framework includes a change applier implementation that most applications use to apply changes to a replica. In this CTP, Sync Framework introduces the change application service, which performs the same actions as the change applier, but in a more granular way. A destination provider that requires greater flexibility than the standard change applier can use the change application service to perform only the set of actions that are required.

For more details please visit the Microsoft download center at:
http://www.microsoft.com/downloads/details.aspx?FamilyID=89adbb1e-53ff-41b5-ba17-8e43a2e66254&displaylang=en

Nina Hu

New Webcast Video - Drill Down Into the Next Release of the Microsoft Sync Framework

liamca — Sat, 02 May 2009 03:14:00 GMT

We recently had a chance to record an MSDN webcast describing a handful of the new features that will ship in the next CTP of Sync Framework v2. This particular session focuses primarily on those features we have built related to our offline and collaboration database scenarios. Please register at the following location:

http://msevents.microsoft.com/CUI/WebCastEventDetails.aspx?culture=en-US&EventID=1032413045&CountryCode=US

This session is a deep dive into the next release of the Microsoft Sync Framework with a focus on our database scenarios. Specifically, this session will discuss some of the work we have done in order to allow developers to synchronize SQL Compact in a peer to peer fashion. In addition, we will discuss the improvements we have made around batching to make it easier to use, expose more control over memory usage and provide resumability over transient networks that go up and down when performing sync operations. Furthermore, we will examine some of the performance related features baked into the runtime to improve the time it takes to initialize your client side database and synchronize large tables that have a less frequent rate of change. This will also include a discussion around some of the lessons we learned when performing scale and performance testing in an environment with 4000 clients and as much as 400 concurrent sync operations on a single server. These best practices were compiled at the end of one of the largest external implementations of the Microsoft Sync Framework in the world. Finally, we will go over some of the new scenarios that we have enabled as a result of building on top of the Sync Framework, which provides much more flexibility around the shape of your topology. These scenarios include taking data stored in SQL Data Services and ADO.NET Data Services offline, USB shuttle scenarios, and traditional scenarios such as branch-office. This session will include demos that provide a deep dive into the use of these features as well as benchmark data around the performance of the Sync Framework in a large distributed environment.

Enjoy and please send any and all feedback our way!

Sean Kelley

Project "Huron" - Early Adopter Program

liamca — Wed, 29 Apr 2009 19:27:00 GMT

I wanted to give an update on our Project "Huron". For those new to it, this is an incubation project that we have been working on for some time to provide database "friction free" (this is a one fo those Microsoft terms that basically means simple to setup :-)) synchronization capabilities to the Cloud (SQL Data Service) via a hosted Sync Service sitting within the Azure data centers. The goal is to remove the typical complexities (configuration, scalability, security, etc) involved with sharing database information between local databases such as SQL Server and SQL Compact and provide simple UI tools for configuration and sync components developers can embed in existing applications.

One unfortunate scoping that we have decided to make is to temporarily hold off on direct support of Microsoft Access for v1. Although we realize that there are a LOT of customers that are looking to support this, based on our current resourcing this has been an unfortunate scoping that we have decided to take. The primarily jusitification was that we already had an existing SQL Server and SQL Compact provider from Sync Framework that we are able to easily re-use which greatly simplified our efforts. It is our hope that some of these Access customers will consider initially linking their Access forms to a SQL Server database to then synchronize via the cloud in the short term until we can provide the full Access support.

The good news is that in the short term we are still planning to offer direct support SQL Server and SQL Compact (desktop and devices). In fact we are very close to the point that we can start taking on some early adopter to verify some of our assumptioms and help us solidify the first release. What we are looking for are any customers that are looking to share SQL Server or SQL Compact databases via the cloud and have an existing project that would warrant this functionality. If you are interested please contact us using the "Email" link in the left sidebar and I can provide additional details.

With that I will leave you with a few screen mock-ups we are working with from our Huron Management Studio Dev UI.

Liam

Custom Conflict Resolution Survey

liamca — Wed, 08 Apr 2009 01:27:00 GMT

We are considering making some changes to the patterns currently leveraged to apply custom conflict resolution policies and business logic. During our design discussions a handful of questions came up, so we thought it would be best to post them on our blog in an effort to collect feedback. Please provide your feedback in the comments attached to this post.

Our questions are as follows:

Can you give a handful of examples when you have had to apply some sort of custom conflict resolution policy and/or your own business logic when syncing changes? Specifically, we are interested in examples that require data to be changed in the middle of synchronization either before/after getting changes or before/after applying changes.
Do you typically leverage the Sync Framework or Sync Services events in order to do so? If so, which events do you most commonly use? If not, can you describe alternate approaches you have taken?
Do you leverage SyncContext to make changes to the DataSet being sent/received or some other approach?

Thank you for your time!

Regards,

Sean Kelley
Program Manager
Microsoft Sync Framework

What's New with Sync Framework

liamca — Mon, 26 Jan 2009 19:37:00 GMT

As a friend pointed out to me a few days ago, I have not provided much of an update on what is going on here in the Sync Framework team since last November. I think sometimes when I am so heads down on a product I can occasionally forget to give you an update on where we are. So I thought I would take a few minutes and let you know what we have been working on (or at least what I can say so far publiclyJ).

Sync Framework v2

Late last year we released a CTP (Community Technology Preview) of Sync Framework v2 and this release had support for things like filtering, simple provider creation and a number of other new features and performance improvements. We are making a lot of progress on this release along with additional new device support. You should expect to see another CTP of Sync Framework v2 before mid-year 2009.

Sync Services for ADO.NET v2

This product has also been a big focus for our group. We had previously released Sync Services for ADO.NET v2 along with Sync Framework v1. In addition we released the device support of Sync Services for ADO.NET. With this we are working quite hard on the next version release of Sync Services for ADO.NET along with some impressive performance testing results that we will be sharing along with this release. I am also dying to tell you about some of the large customer successes that we have been working with, but unfortunately I have to wait until their product actually ships. L

Project “Huron”

This project has been a large focus of mine for quite some time now. I am really pleased at how things are progressing with this project and hope to present some more of this to you in the next few months. I love the concept of being able to take any database on any device and with no work (or development) publish that data to the cloud and then invite others to subscribe to that data into a database of their choosing (on the device of their choice) and then share and contribute to it without having to worry about the authentication, security or scalability of your “data hub”. As you might imagine we have been working quite closely with the SQL Data Services team on this project to become our customer data hub in the cloud.

SyncToy 2.0

SyncToy is a free file synchronization utility that uses Sync Framework under the covers. This product along with the related “Anchorage” project is managed within our Sync Framework team. SyncToy just had its biggest month ever with a total of 136,610 downloads for the month of December putting it in the top 50 downloads of all Microsoft products!

So that is just a few of the things that have been keeping our team busy. So to Mike and the others who kindly read this blog on a regular basis, I will try to better on keeping you up-to-date on where we are!

Liam

Now Available - Sync Services for ADO.NET on Windows Mobile (Devices)

liamca — Tue, 16 Sep 2008 19:38:00 GMT

We are now announcing the availability of v1.0 Service Pack 1 of Sync Services for ADO.NET on Devices (Windows Mobile).

"Microsoft Synchronization Services for ADO.NET 1.0 provides the ability to synchronize data from disparate sources. Rather than simply replicating a database and its schema, the Synchronization Services application programming interface (API) provides a set of components to synchronize data between data services and a local store. Applications are increasingly used on mobile clients, such as laptops and devices that do not have a consistent or reliable network connection to a central server. It is crucial for these applications to work against a local copy of data on the client".

"Equally important is the need to synchronize the local copy of the data with a central server when a network connection is available. The Synchronization Services API, which is modeled after the ADO.NET data access APIs, gives you an intuitive way to synchronize data. It makes building applications for occasionally connected environments a logical extension of building applications where you can count on a consistent network connection".

Synchronization Services for ADO.NET 1.0, which released with Visual Studio 2008, enabled synchronization between a server database and a SQL Compact 3.5 client database running on a desktop. With this download, you can also synchronize between a server database and a SQL Compact database on a Windows Mobile 5 or 6 device.

2 New Sync Samples - Download Only & Adapter Builder

liamca — Wed, 13 Aug 2008 02:09:00 GMT

We have just posted the following two new samples to the Sync Code Gallery today for Sync Services for ADO.NET v2:

Download Only Sync
This sample demonstrates two-tier download-only synchronization using Microsoft Sync Services for ADO.NET v2.0. The sample solution is composed of two projects: Client, which includes the UI form, data access code, and synchronization agent code for Sync Services; and SampleServerSyncProvider, which includes server synchronization provider code for Sync Services. For more information, see the code comments that are included in each file.

Sync Adapter Builder
This sample utility demonstrates how to create synchronization commands by using the SqlSyncAdapterBuilder in Microsoft Sync Services for ADO.NET v2. The sample solution is composed of one project that includes the UI form, data access code, and SqlSyncAdapterBuilder code. The SqlSyncAdapterBuilder is typically used at run time to generate synchronization commands, which are in the form of SQL queries. This provides an alternative to writing these commands manually at design time. In this sample, we use the SqlSyncAdapterBuilder to output synchronization commands. You can output commands that work with SQL Server change tracking (available in SQL Server 2008) or a custom change tracking system. Running this application enables you to see how the commands are structured, and to copy those commands for use in applicatons where you will specify commands manually.

Liam

Sync Case Study - ServiceU Corporation & Event Management

liamca — Fri, 08 Aug 2008 01:55:00 GMT

One of the best parts about getting our first version of Sync Framework out the door is that we can now start talking about some of the customers we have been working with over the past few months and some of the great solutions that they are building.

Beyond the customers I mentioned earlier (SmugMug, InterScape, Fujitsu Siemens) I also wanted to point you to another customer called ServiceU Corporation. This company is a leader in the field of supporting online and on-demand event management. As you will read in the case study:

"Its software services, created and deployed using the Microsoft® Application Platform, are used by churches, schools, universities, theaters, and businesses to manage concerts, conferences, and other events. As a Payment Card Industry Level 1 Service Provider, the company is interested in security and performance, which is why it is upgrading to Microsoft SQL Server® 2008. ServiceU is using a number of new SQL Server 2008 features including enhanced auditing, and Policy-based Management to enforce configuration policies. The company is also using the new Performance Data Collection and Plan Freezing features to enhance performance, and the Data Compression and Backup Compression features to reduce the cost of disk-based storage".

To help power this solution, ServiceU chose Sync Services for ADO.NET:

"Working from Visual Studio 2008, developers can use Microsoft Synchronization Services for ADO.NET 2.0 to synchronize data from disparate sources over multi-tier and service-based architectures. ServiceU likes this feature because it is interested in deploying more solutions that run on mobile and remote devices. “Whenever you have server-based, data-driven applications coordinating data with mobile devices, synchronization is essential,” says Smith. “Synchronization Services will be a great help as we develop new occasionally-connected solutions to offer to our customers.”

Over the next few months we will be talking more and more about some of the great companies that are using Sync Framework and Sync Services for ADO.NET.

Of course, given that our technology is free and readily downloadable from the web, we don't hear from every customer. As such, if you are using any of these technologies please let me know (at the Email link on the sidebar) so we can share your success with the rest of the community.

For more details on this case study, please go to: http://www.microsoft.com/casestudies/casestudy.aspx?casestudyid=4000001258

Liam

Top New Features in Sync Services for ADO.NET v2

liamca — Wed, 06 Aug 2008 20:07:00 GMT

Today’s release of Microsoft Sync Framework includes the latest version of Sync Services for ADO.NET. A great deal of work has gone into this release and I thought I would take some time to point out some of the top new features in version 2 since our previous release.

Peer-to-peer synchronization support:

Beyone the traditional hub-and-spoke synchronization support built into Sync Services for ADO.NET. v2 now supports peer-to-peer synchronization. The focus with this part of the API is collaborative applications. For example, in an application that allows users to share project notes, project team members often require a local copy of data that they can work with. When they have made changes, they can synchronize with another team member to exchange changes.

Sync Services is now based on Microsoft Sync Framework:

Sync Services now uses Microsoft.Synchronization.dll. If you installed Sync Services by using SyncSetup.exe, this DLL is already installed. This enables Sync Services for ADO.NET to take advantage of all the features and capabilities built into the Sync Framework.

Synchronize with devices:

Sync Services for ADO.NET 1.0 enabled synchronization between a server database and a SQL Server Compact 3.5 database on the desktop. Now, you can also synchronize between a server database and a SQL Server Compact 3.5 database on a device.

Support for SQL Server 2008 Integrated Change Tracking:

If you are using SQL Server 2008, Sync Services for ADO.NET has the ability to take advantage of the new SQL Server integrated change tracking feature. This feature addresses many of the issues of custom-tracking systems and provides a straightforward way to track changes. Change tracking is also supported by the Local Database Cache in Visual Studio 2008 SP1. Developers can now specify that the Configure Data Synchronization wizard should enable SQL Server change tracking on the server and generate the commands necessary to select and apply changes to the server database. Unlike custom change tracking systems, SQL Server change tracking does not require any schema changes in the server database.

Support for the new data types in SQL Server 2008:

Sync Services for ADO.NET has added support for a number of new data types including those added in SQL Server 2008.

The ability to trace the synchronization process:

In distributed applications, tracing can be crucial because it enables you to troubleshoot issues that might otherwise be difficult to identify. Sync Services includes tracing for the client and server synchronization providers.

Liam Cavanagh

Announcing Availability of Sync Framework v1 and Sync Services for ADO.NET v2

liamca — Tue, 05 Aug 2008 20:08:00 GMT

I am happy to announce the general availability of Sync Framework v1 and Sync Services for ADO.NET v2. As of today you can download the Sync Framework SDK in 11 languages including Chinese (Hong Kong), Chinese (Simplified), English, German, French, Italian, Japanese, Korean, Portuguese, Russian and Spanish for AMD64, IA64 and x86 processors from the Sync Framework Download Center.

What is Sync Framework?

Imagine being able to build a solution that seamlessly exchanges contact information between Outlook, a database contact management application, your mobile device and your service based contact management system. Or how about a mobile device that connects with other devices to exchange pictures and videos. How about being able to take data from any of your enterprise databases, file or enterprise systems and make it available offline for users to modify and sync back up to the enterprise. All of these capabilities are possible with the Sync Framework and best of all, it is free on Windows platforms and licensable on non-Windows platforms!

Just a few examples of companies that are already using the Sync Framework include:

SmugMug who has added support for the Sync Framework to enable developers to build rich offline applications that can allow photos to be easily shared on friends and families local computers.
InterScape have embedded Sync Framework into their Customer Relationship & Management (CRM) solution to enable sales people to synchronize enterprise files and data for offline access.
Fujitsu Siemens will embed the SyncToy file synchronization solution (powered by Sync Framework) on their STORAGEBIRD external drives to enable seamless file synchronization between devices and computers.

Sync Framework Highlights

Some of the highlights of this release include:

Sync support to new and existing applications, services, and devices
Collaboration and offline capabilities for any application
Roam and share information from any data store, over any protocol, and over any network configuration
Leverage sync capabilities exposed in Microsoft technologies to create sync ecosystems
Extend the architecture to support custom data types including files

Sync Services for ADO.NET v2 Highlights

Sync Services for ADO.NET is a Microsoft Sync Framework powered solution for synchronizing ADO.NET enabled databases in offline and collaboration scenarios. Sync Services for ADO.NET allows developers who are familiar with the concepts of ADO.NET to apply that knowledge to data synchronization through a very similar set of APIs to that of ADO.NET. Sync Services for ADO.NET provides the flexibility of a programming model like offline datasets and a richer synchronization feature set like that found in Merge replication. Sync Services for ADO.NET also supports synchronization over services, such as Windows Communication Foundation (WCF).

Some of the Sync Services for ADO.NET highlights include:

Offline Database Synchronization: With Sync Services for ADO.NET you are able to build a solution where multiple remote clients connect and synchronize to a central ADO.NET database in a Hub-and-Spoke configuration. This enables occasionally connected devices to periodically connect and synchronize changes with a central ADO.NET database server. This topology is a common solution for remote workers such as sales reps or field service workers.
Collaboration Between Databases: Sync Services for ADO.NET also includes Peer-to-Peer capabilities. Through a custom Peer provider, collaboration between two or more SQL Server databases can occur (support is not available for SQL Server Compact). Unlike a Hub-and-Spoke architecture, this provider enables a SQL Server database to communicate and exchange information with any other SQL Server database. This type of scenario is useful in group scenarios where users (such as auditors) need to update information and then collaborate those changes with other group members.
SQL Server 2008 Integrated Change Tracking: If you are using SQL Server 2008, we recommend that you use the SQL Server change tracking feature. This feature addresses many of the issues of custom-tracking systems and provides a straightforward way to track changes. Change tracking is also supported by the Local Database Cache in Visual Studio 2008 SP1. Developers can now specify that the Configure Data Synchronization wizard should enable SQL Server change tracking on the server and generate the commands necessary to select and apply changes to the server database. Unlike custom change tracking systems, SQL Server change tracking does not require any schema changes in the server database. For more information, see the Visual Studio 2008 documentation.

Sync Framework Pricing

Sync Framework will be licensed free on Windows platforms. In addition, we are also licensing the specifications and a source code porting kit to developers who want to implement Microsoft Sync Framework solutions on non-Windows platforms.

To learn more, visit http://msdn.microsoft.com/sync

I also want to send a special thank-you to those of you who have provided feedback throughout our CTP's and have helped make this a great release!

Liam Cavanagh

Using SQL Server 2008 Integrated Change Tracking to Optimize Data Synchronization

liamca — Thu, 26 Jun 2008 00:09:00 GMT

I thought I would take the chance to talk to you a little bit about a major enhancements we have made with synchronization in SQL Server 2008. The feature I am referrring to is called SQL Server 2008 Integrated Change Tracking.

The idea behind this feature is that it enables SQL Server to track data changes to your database rather than relying on you to create a change tracking technique.

Why is this feature so great? Well in my experience I have found that DBA's are less then enthusiastic when you tell them that in order to track changes, they will need to add triggers to each of the tables. Then they will either need to add an additional tracking column to that table (or to a separately linked table) and will need to create one tombstone table per table to track deletes. Oh, and by the way these triggers will need to be fairly complicated because you really need to deal with all of the isolation issues that come along with proper change tracking... and cross your fingers that these changes do not affect your existing applications. Not a fan of that idea? I am not surprised.

Well with SQL Server 2008, you can now simply turn on an option to enable change tracking. Then you tell SQL Server which tables you want it to monitor. From that point SQL Server will start monitoring these changes and store them in a separate change tracking table which you have access to. If you want to get the changes since a certain point in time you simply join the ChangeTable to your base table and presto you have all of the inserts, updates and deletes.

As an added bonus, this feature has been integrated into the existing Visual Studio SP1 beta that is now available for download. Guy Burstein has a great summary of this feature and I am going to steal one of his screen shots below.

As you can see from the screen shot, Visual Studio will detect if you are using SQL Server 2008 and let you choose to automatically enable change tracking for the tables you have selected to synchronize.

After you have selected change tracking, Visual Studio can go out and make the changes to your database for you. Of course, you still have the option to use the previous method of Change Tracking using triggers with SQL Server 2008. Visual Studio will still make those changes to your database to support change tracking, however given the performance of integrated change tracking and the added simplicity I think there will be very few times when the previous technique will be used.

Liam Cavanagh

Sample - SQL Express Client Synchronization using Sync Services for ADO.NET

liamca — Tue, 24 Jun 2008 19:40:00 GMT

We have just posted a new sync sample to our Code Gallery that demonstrates how to enable offline data collection applications to synchronize a SQL Express client database to another SQL Server database using the Synchronization Services for ADO.NET library. In this scenario, SQL Express client databases can be used as client databases to a central ADO.NET enabled database. Unlike the existing peer-to-peer synchronization SQL Express provider sample which you may have seen, this sample is optimized for a hub-and-spoke topology.

In this sample, two tables (orders and order_details) are on the server database and also on the local client database. The sample synchronizes edits to these table to keep their data identical.
This sample demonstrates:

Using SQL Express to cache changes for a client application.
A customized SQLExpressClientSyncProvider class that wraps around Microsoft.Synchronization.Data.Server.DbServerSyncProvider.

I would like to point out that even though we have done a fair amount of testing in house with this sample, it is still only posted as a sample. In the future we certainly plan of including a fully supported version of a SQL Express client provider within a future release of Sync Services for ADO.NET.

With that, we certainly want to hear your feedback on this sample and please feel free to post comments to our Sync Services for ADO.NET forum.

Liam Cavanagh

Extending Visual Studio 2008 SP1 Sync Designer to Support Bi-Directional Synchronization

liamca — Tue, 17 Jun 2008 00:18:00 GMT

The following is an excerpt from the documentation updates that will be occurring for Visual Studio 2008 sp1. We have decided to post this content early due to the significant amount of interest expressed around this particular topic. Specifically, this section describes how one would go about extending the sync designer generated code to support bi-directional sync scenarios where changes made on the client-side database are pushed back up to the server. The intent of this documentation is to provide an introductory walk-through and samples. For a more in-depth discussion around bi-directional synchronization, please see the following run-time docs:

http://msdn.microsoft.com/en-us/library/bb726007(SQL.100).aspx

Please let us know if you have any feedback.

Sean Kelley

Announcing Sync Framework v1.0 RC0 and Sync Services for ADO.NET v2.0 RC0 [Updated]

liamca — Tue, 10 Jun 2008 01:12:00 GMT

With the completion of TechEd 2008 for Developer we have one last big announcement to make. A Release Candidate (RC0) of Sync Framework v1.0 and Sync Services for ADO.NET v2.0 for Desktops and Servers is now available.

These components can be found as a top level feature within SQL Server 2008 RC0. RC0 is the final step before SQL Server 2008 RTMs in Q3 of this year.

SQL Server 2008 RC0 can be downloaded from the Microsoft Download Center at:

SQL Server 2008 Release Candidate 0

For MSDN and TechNet Plus subscribers, after logging into their respective accounts, subscribers can view Product Keys and download SQL Server 2008 RC0 from the following links:

Download SQL Server 2008 RC0 (MSDN subscribers)

Download SQL Server 2008 RC0 (TechNet Plus subscribers)

As we announced at TechEd, we are also targeting a CTP (Community Technology Preview) of the Sync Framework on devices for Q3 2008.