CRM has several deployment wide settings which are stored in the DeploymentProperties table in the configuration database (usually MSCRM_CONFIG). It is not recommended to modify the values in the table directly you may sometimes need to change values. The recommended method is usually to use a PowerShell script.
Some of the settings are described in the following table. I will add to the table as I discover settings.
|Controls whether updates are applied to organization databases immediately when an update rollup is installed or deferred for manual installation