1. Patch Uninstall Custom Actions

2. 11/22/2015Microsoft Confidential2 Requirement: Support for patch uninstall custom actions Patch Uninstalls and Custom Actions SQL Patch SQL Install SQLApply a SQL Patch In addition to patching the database engine, the patch runs custom actions that create new tables that are valid only for this version of the engine. Uninstall the SQL Patch SQL There is no way for the patch being uninstalled to run a custom action. This means state of the system not truly back to pre-patched state. Design Change: Provide a new custom action type that can be run during a patch uninstall

3. Anatomy of a Windows Installer Patch Target MSI Target Files Upgrade MSI Upgrade Files MSP Transform Target to Upgrade Payload Target MSI + Transform = Upgrade MSI Payload = Σ(Upgrade File - Target File)

4. Patch Uninstall Custom Actions: Under the hoods MSI Datastore SQL Cached SQL MSI Install SQL Apply a SQL Patch Cached SQL MSP Uninstall the SQL Patch SQL 6.0 SQL Patch Custom actions to patch and un-patch the database SQL 6.1 Cached SQL MSI SQL MSP In-memory SQL MSI with the patch CA New Table In-memory SQL MSI with the un-patch CA Cached SQL MSP