关于 SQL Server Compact 3.5 Beta2 的发布

SQL Server Compact 3.5 Beta2 和 Synchronization Services for ADO.NET 已经包含在上周发布的 Visual Studio 2008 Beta2 中，它们会随着 Visual Studio 2008 Beta2 安装到你的计算机上。不过由于进度的原因，Visual Studio 2008 Beta2 并没有包含它们的联机丛书，需要单独下载和安装：

Server Compact 3.5 Books Online for Orcas Beta 2
Synchronization Services for ADO.NET Books Online Beta 2

今天微软发布了 SQL Server Compact 3.5 Beta2 的独立安装包，分为 Windows Desktop 和 Windows Mobile 两个版本。

SQL Server Compact 3.5 for Windows Desktop Beta 2
SQL Server Compact 3.5 for Windows Mobile Beta 2
SQL Server Compact 3.5 Replication Server Tools

其中 Windows Desktop 版本的安装包中包含了 Synchronization Services for ADO.NET。很遗憾的是，一直期待的 Windows Mobile 版本的 Synchronization Services for ADO.NET 还没有出来，而且确切的工作计划才刚刚确定。根据 Steve Lasker 的回复，SQL Server Compact 3.5 RTM 也不会有 Windows Mobile 版本的 Synchronization Services for ADO.NET。估计要等到 SQL Server Compact 3.5 SP1，那时候和 SQL Server 2008 一起发布。

另外，Visual Studio 2005 目前不支持 SQL Server Compact 3.5 的可视化设计，在 Visual Studio 2008 中支持。

SQL Server Compact 3.5 的新特性包括：
·LINQ to SQL enabling developers to integrate data access directly into their code
·Ithe timestamp (rowversion) data type. rowversion is a data type that exposes automatically generated binary numbers, which are guaranteed to be unique in a database. It is used typically as a mechanism for version-stamping table rows.
·Supports local transaction scope on a desktop and Tablet PC.
·Table Designer in Visual Studio 2008 has been enhanced to provide a user interface for creating primary key and foreign key relationships between tables.
·Support for transact-SQL statements has been extended as follows:
··Nested query in SELECT FROM clause
··CROSS APPLY and OUTER APPLY
··CAST
··TOP
·Supports data replication with SQL Server 2005 by using Microsoft Synchronization Services for ADO.NET. Synchronization Services is available for desktop and Tablet PCs only.
·Can be used for developing SQL Server Compact 3.5 desktop and Tablet PC applications by using Visual C# 2008 Express Edition and Visual Basic 2008 Express Edition.
·Can be installed side-by-side with the previous version on desktop and Tablet PC computers. Using SQL Server Compact 3.5, you can open database files (*.sdf) created in the previous version (3.1). Be aware that when a database file is opened in SQL Server Compact 3.5, the file is updated to 3.5. You will no longer be able to open the database by using the 3.1 version. Databases created by using SQL Server Compact 3.5 cannot be opened by earlier versions of SQL Server Compact 3.5.

参考：
SQL Server Compact 3.5 B2 & Sync Services for ADO.NET Documentation released
SQL Server Compact 3.5 B2 released
SQL Server Compact 3.5 B2 Books Online