Something very important to keep in mind, which is not mentioned in the documentation of in most articles that the [Input Transformation Policy Set], the [Output Transformation Policy] and [Schema Mapping Policy] are NOT part of the subscriber and publisher channels.

EVERYTHING coming from the application side will pass through input transforms and schema mapping and EVERYTHING that gets send on to the application will run through [Schema Mapping Policy] and output transform. 

This includes queries and their search results as well as status messages and direct, out-of-band object modifications. Even part of the driver start-up communication will pass through these.

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