Is it possible to update a DirectX SDK install?

Is it possible to update a current install of the DirectX SDK, or is the only way to use the latest SDK to install the latest SDK in a new directory and delete the old one?

Specifically, if I have DirectX (March 2009), and the l开发者_如何学Goatest version is DirectX (August 2009), what choices do I have for getting the updated SDK without leaving the old SDK installed?

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The install can live together, and install in separate space. You have to uninstall the old one, and install the new one, otherwise you'll use double space.

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Edit: Seems I was wrong. Sorry.

I'm pretty sure an install of the new sdk will override the former sdk install. That means you only have to install DirectX(August 2009) and it should take care of the rest.