https://community.appian.com/discussions/f/data/17745/what-exactly-rp-id-containsHi, We are trying to create Expression based Record by getting the date from View. Written expression rule to return todatasubset with different identifiers mapped other than Primary id. primary key for the resultant cdt is different from the todatasubseten-USTelligent Community 12https://community.appian.com/thread/69898?ContentTypeID=1Fri, 11 Oct 2019 19:56:00 GMTd3a83456-d57b-489c-a84c-4e8267bb592a:f9d07468-20ca-401d-b513-6a0f9d063efcramp<p>Thaks for the prompt response. now got the clarity.</p><div style="clear:both;"></div>https://community.appian.com/thread/69879?ContentTypeID=1Fri, 11 Oct 2019 01:14:16 GMTd3a83456-d57b-489c-a84c-4e8267bb592a:2f38d819-28b8-432c-b787-062b941ddadaTJ<p>Hi,</p> <p>Could you use a!datasubset() rather than fn!todatasubset. The new function provides you ability to specifically define your identifiers i.e. rp!id<br /><br /></p> <p>Trust this would solve your query.</p><div style="clear:both;"></div>https://community.appian.com/thread/69876?ContentTypeID=1Thu, 10 Oct 2019 21:01:15 GMTd3a83456-d57b-489c-a84c-4e8267bb592a:7e53f9dd-ae8b-46d5-96b5-53f8b26bea5fPeter Lewis<p>rp!id will return the value of the identifier for the current record. For example, suppose you have an expression-backed record that contains a list of cases, with fields called caseId and caseNumber. If I choose caseNumber as the data in the identifiers property, that is what will be used as rp!id, even if caseId is the primary key of your source CDT.</p> <p>That being said...is there a reason that you don&#39;t just make them the same thing? It seems likely that it will lead to confusion if you use a different field :)&nbsp;</p><div style="clear:both;"></div>