List of time retrieval options

After

Returns the first recorded value after the time requested by the client application.

At or After

Returns a recorded value at the time requested by the client application. If no value exists at the specified time, returns the next recorded value.

At or Before

Returns a recorded value at the time requested by the client application. If no value exists at the specified time, returns the previous recorded value.

Automatic

A continuous point (step attribute = 0) is treated as Interpolated, whereas a discrete point (step attribute = 1) is treated as At or Before.

Before

Returns the first recorded value before the time requested by the client application.

Exact Time

Returns a recorded value at the time requested by the client application. If no recorded value exists at that time, an error is returned.

Interpolated

Returns an interpolated value for the time requested by the client application. Discrete points (step attribute = 1) carry the previous value forward.

Not Supported

Used in time range calculations only. If the client application sends a time instead of a time range, PI AF returns an error message as the attribute value.

Time Range

Used in time range calculations only. Creates a default time range to use if the client application sends a time instead of a time range. If you choose this option, you must type a PI relative time expression in the Relative Time field. See Create default time ranges for element attributes for details.

Time Range Override

Used in time range calculations only. Specifies a time range that always overrides the time range supplied by the client application. You can specify:

• A fixed duration, as described in Create ranges of configurable durations.

• A dynamically calculated duration, as described in Configure dynamic time range calculations.