An Incremental Servicing Model is available from the SQL Server team to deliver hotfixes for reported problems

On-demand (OD)

• The issue must meet certain criteria for this request. These include a lack of an effective workaround, a critical business effect, and so on.
• The hotfix can be requested by any customer, regardless of their support offering, as long as it meets the criteria for the request.
• The hotfix is released on or before a mutually agreed upon date based on the customer’s need.
• This hotfix build can contain one or more fixes.

Cumulative update (CU)

• The update can be requested by any customer, regardless of their support offering.
• The update is released every 2 months.
• The update contains the following:
  
  • All previous critical on-demand hotfixes to date.
  • Fixes for issues that meet hotfix acceptance criteria. These criteria include workaround availability, customer effect, reproducibility, the complexity of the code that must be changed, and so on.

General distribution release (GDR)

• A GDR addresses an issue that has a broad customer impact, that has security implications, or that has both. A GDR is determined and issued by Microsoft as appropriate and when appropriate. GDRs are kept to a minimum.
• A GDR cannot be requested by a customer. Microsoft internally determines whether a reported hotfix is classified as and delivered as a GDR.
• A GDR is released through the download center. A GDR is also released through Microsoft Update, through Windows Update, or through both.

By default, all hotfixes are serviced through GDR releases, through CU releases, and through COD releases. When a product’s hotfix request volume falls under a certain threshold, such as ten hotfix requests per month, the SQL team stops CU releases and delivers hotfixes through GDR releases, through OD releases, and through COD releases. The SQL Server team makes the determination based on support costs and on customer demand.

The following figure shows an overview of the ISM support cycle for a typical product. Both the original release version support cycle and the first service pack support cycle are shown. This kind of timeline also applies for all future releases of a product. For example, the timeline applies between Service Pack 1 and Service Pack 2. The timeline applies for all products in the support matrix. Be aware that different products may have different periods between the original release version and the first service pack release. GDRs and CODs can occur during the support life cycle of a product.

With a non-ISM servicing model, rollup releases after a major release cover the servicing gap that occurs between an earlier release and a current release. For example, rollup releases cover the gap that occurs between the original release version and the Service Pack 1 releases. Because an ISM eliminates servicing gaps, an ISM eliminates the need for hotfix rollup releases. The first CU after a new release contains the hotfix rollup, plus any additional QFEs.

A hotfix package does not replace a service pack. A hotfix package is optional. A hotfix package can be installed or uninstalled at any time. Additionally, hotfix packages are cumulative. Therefore, the latest OD hotfix package or CU hotfix package includes all previously released hotfixes.

The SQL Server team is introducing this revised model while focusing on ways to improve the quality of SQL Server to reduce the need for hotfixes.