Compare sql server 2005 and 2008 by SharePoint 2010

You can use both Sql server 2005 and sql server 2008 with sharepoint 2010 but what are the advantages or disadvantages .

Absolutely i recommend use SQL Server 2008 r2 for sharepoint 2010 products. Here is the why i choose it

Performance and Avaiblity :SQL Server 2008 R2 Enterprise edition enables several dimensions on which it can scale, enabling even the most demanding SharePoint Server 2010 deployments. For example, rapidly growing Enterprise Content Management (ECM) or Web Content Management (WCM) workloads may often require compute resources beyond those associated with traditional collaboration scenarios. SQL Server 2008 R2 Enterprise can support this scenario through a number of improvements, by enabling greater processor scale, the ability to address more physical memory on 64-bit hardware, and hot-add hardware support.

Business Continuity Management is a combination of high availability and disaster recovery. High availability ensures a certain absolute degree of operational continuity in the event one or more components fail in an isolated location. Availability requirements are defined by Operating and Service Level Agreements. Disaster recovery ensures a certain absolute degree of operational continuity in the event that all systems fail in one or more locations. Disaster recovery requirements are defined by Operating Level Agreements, Recovery Point, and Recovery Time Objectives.

SQL Server 2008 R2 provides a number of native capabilities to enable the design and deployment of a highly available SharePoint Server 2010 deployment including database mirroring, failover clustering, and log shipping.

SQL Server 2005 mainstream support will end fairly soon (read more athttp://support.microsoft.com/gp/lifesupsps)

Security: Transparent Data Encryption (TDE) is a feature added in SQL Server 2008 Enterprise that performs real time I/O encryption and decryption of data and log files without requiring unsupported modification of the underlying table schema or increasing the size of the database—that means no changes to SharePoint to enable TDE SQL server audit.Server Audit, which enables tracking and logging events that occur on the system, for example detecting changes or modifications to database objects/stored procedures, surfacing changes to server configuration settings, or detecting changes to audit configuration settings.

Better Reporting Services:SharePoint Server 2010 and SQL Server 2008 R2 Enterprise provide close business intelligence capabilities integration through SQL Server Reporting Services. Using SQL Server Reporting Services, administrators can configure reporting servers to enable real-time access to information and control who has access to that information. End users can benefit from this integration by publishing SQL Server reports directly to Document Libraries or by optionally embedding reports in pages hosted on one or more sites in a Microsoft SharePoint Server 2010 deployment.

To learn more about Reporting Services in SQL Server 2008 see SQL Server Reporting Services (http://msdn.microsoft.com/en-us/library/ms159106.aspx).

Using FileStream Functionality with 2008:Remote Blob Storage integration with SharePoint Server 2010 in SQL Server 2008 R2 Enterprise enables an administrator to externalize SharePoint binary large object (BLOB) data by hosting it on less expensive, commodity hardware solutions and managing it with SQL Server through the same data management techniques they use today. Remote Blob Storage can be an integral component in the most stringent compliance scenarios by enabling third-party technologies to implement solutions such as expunge on the server(s) hosting the externalized BLOBs
see:https://blog.bugrapostaci.com/2010/10/01/sharepoint-2010-server-with-filestream-rbs-provider/

Sharepoint Server 2010 Fuctionality and SQL Server Eddition Comparison

Resources:
http://technet.microsoft.com/en-us/library/cc990273.aspx
http://technet.microsoft.com/en-us/library/cc262749.aspx

Other:

http://sqlcat.com/top10lists/archive/2009/02/24/top-10-performance-and-productivity-reasons-to-use-sql-server-2008-for-your-business-intelligence-solutions.aspx