In the pi Toolkit, there are a number of functions to return archive calculations such as total, minimum, and standard deviation. In the PI-API these have been condensed into one function, piar_summary, in which a mode parameter specifies the appropriate calculation.
Three functions which allow archive modification, (limited to the pi home node in the pi Toolkit) are provided in the PI-API. The routines piar_putvalue, piar_replacevalue, and piar_deletevalue are typically used with laboratory data, allowing an application to insert values directly into the Archive, modify existing values, or delete values, respectively. Process data should still be inserted into the Archive via the Snapshot with pisn_putsnapshot or preferably by pisn_sendexceptions.