Question
Kavileswar
IN
Last activity: 30 Dec 2016 5:36 EST
What kind of technique backward chaining uses
Does Backward chaining implicitly uses "Back Tracking" technique to get the previous value if no current value at the time of refering target property.Back Tracking solves N-Queens problem, i think Pega follows the same approach here too.
***Updated by moderator: Lochan to add Categories***
Pegasystems Inc.
IN
Hello!
I found this info in the Help doc - Backward chaining
Does this help?
Regards,
Lochan | Community Moderator | Pegasystems Inc.
Kavileswar
IN
Am looking for what technique backward chaining uses internally
Accepted Solution
PEG
IN
Hi,
PRPC uses inference engine in background.
The inference engine and declarative network
Internally, Pega 7 Platform uses an inference engine and the declarative network to support declarative processing. Two properties A and B are linked in the network if the value of A depends on the value of B.
Inference engine processing operates invisibly in the moment between activity step executions. The step most recently executed may have changed a property value (and cause forward chaining, defined below), or may have updated the database (and cause Declare OnChange processing). The next step may need a property value that is not yet defined, which causes backward chaining to start.