Agent Modes

This page discusses the various agent modes used during processing.

Get processing

TBD

Set processing

SET_RESERVE1

The purpose of SET_RESERVE1 is to try and detect invalid SET requests as soon as possible. If any of the columns are assigned an impossible value (wrong type, or out-of-range, etc), then the request fails.

SET_RESERVE2

The purpose of SET_RESERVE2 is to set up/allocate the data structure for a new row or perform any resource allocation needed for further processing (e.g. database locks).

SET_FREE

The purpose of SET_FREE is to undo anything done in the two SET_RESERVE passes, if some aspect of the request proves unacceptable. This means possibly releasing the data structure for a new row, if one has just been created.

SET_ACTION

SET_ACTION assigns the appropriate column values to the data structure for this row (either the new structure created in the SET_RESERVE2 step, or an existing row structure).

SET_UNDO

SET_UNDO reverses anything done in the two SET_RESERVE steps or SET_ACTION - called if some part of the SET_ACTION processing fails. This is similar to the SET_FREE processing, but also needs to reverse any newly assigned values.

SET_COMMIT

The purpose of SET_COMMIT is to confirm that the processing of the SET request has completed successfully, and perform any "irreversible" actions.

Baby Steps

TBD