Hi @alexAguilarMx ,

You are on a correct way. Existing records can be reprocessed by using either PARTIAL or FULL reprocess operation.

The Reprocess All Entities checkbox simply says: Run the reprocess operation on ALL entities in your model (both instance and master layer). Meaning all records in your MDM hub will be run through the processing again.

Either use the option "Reprocess All Entities" or select entities to be reprocessed in the Entities to Reprocess section.

The Rematch All / Selected Entities is a supplementary option to the Reprocess. It restarts the matching process on reprocessed records. By default the engine keeps the identity as originally assigned. If REMATCH enabled, the matching results are recalculated.
WARNING! Performing the rematch action means, the manual match exceptions entered by any user will be removed and matching will be recalculated!!!

Just keep in mind that the FULL reprocess operation might take some time - similar to the INITIAL load.

BTW You can read more about parameters in the configuration UI when you mouse over the label.

Hi ​@Ales 
I have a follow-up question, if you can help me with it.
Do previously matched records remain even after rematch if the match logic has changed?

Hi ​@aish_TF ,

this is a very good question. The simple answer would be YES, they should remain in the same groups if you don’t change the rules, HOWEVER

Imagine a situation where you INCREMENTALLY process your data. Some records coming in different loads and matching to existing groups.

The engine keeps the existing identities as they are unless you do the rematch. You may have existing master record A and existing master record B, a new record comes and fit to both A and B.

In the delta load the record will match to either A or B and make a proposal to the second one.

So if you rematch ALL records together it may happen that both A, B and the new one will create one single group. Simply because they now have the connecting points between them and they are allowed to match together.

Hope that answers your questions.

Ales

​@Ales Thank you for your answer. I get it.
But why does it get updated with a new match rule name?
For example,
There are two records, lets say A and B, that matched in a previous match processing and the match rule was rule3
In the next rematch for ALL records, A matches C and B matches D by rule2. Now, B also matches E but rule1. So all these 5 records form a group.
But the rule names I see are rule2 for A,B,C,D and rule1 for E. How is this determined? And is there a way to see and export that historically A and B matched as per rule3? 

Thanks once again. :)