Retrieval Mode (Core Services)

The retrieval mode is an enumeration of the possible values for retrieving recorded values from a stream. The following values are accepted:

• Auto

  Automatically determine the best retrieval mode.

• AtOrBefore

  Return a recorded value at the passed time or if no value exists at that time, the previous recorded value.

• Before

  Return the first recorded value before the passed time.

• AtOrAfter

  Return a recorded value at the passed time or if no value exists at that time, the next recorded value.

• After

  Return the first recorded value after the passed time.

• Exact

  Return a recorded value at the passed time or return an error if none exists.