SharePoint 2010 - What new in PATCHING SharePoint 2010

Patching is referred to as a build-to-build or b2b upgrade, as it is only upgrading to a newer build of the same version

One of the most great improvements in patching with SharePoint 2010 is that the binaries on your farm can be at a newer version than the databases those binaries are using, if both builds are in the same compatibility range.

The compatibility ranges should be between service packs, meaning that any database that is SharePoint 2010 SP1 or higher should be able to be rendered by binaries that are at the same build or later, but before SP2. This gives you the freedom to upgrade your binaries without immediately upgrading your databases at the same time. Walking through all your databases and upgrading them is the most time intensive part of patching, so being able to postpone that is a huge advantage.

Meaning you’ll be able to patch the binaries running on your servers quickly and take advantage of any fixes or security updates without having to incur the downtime penalty of upgrading

your databases too You can postpone the lengthy database upgrade part to a more convenient

time, like over the weekend.This is especially handy if you have user bases in different time zones. While you shouldn’t plan on leaving your farm in this condition for weeks or months, you can safely do it for a few days.

Once you decide to upgrade the databases then run the command "Upgrade-SPContentDatabase" with the name of the specific database, And as like "Mount-SPContentDatabase" you can run multiple instances of the upgrade command.

Not only can your databases be out of sync with the binaries installed on your server, but the servers themselves can be at different build levels as well. This is truly an advanced move, however, and should only be used when necessary by trained professionals. If you do choose to patch your servers individually it’s recommended that you do tiers of them at a time. For example, if you have several servers running the Search component, try to keep their patch level in sync. If you have multiple web front ends (WFEs), keep them in sync or all search servers in sync etc.