https://community.qlik.com/t5/App-Development/date-key-issue/m-p/1985028#M81301 <P>Maybe FILE_REGD_DATE is not properly formatted in both tables. </P> <P>Try with these</P> <P>&nbsp;Num(Date#(FILE_REGD_DATE, 'MM/DD/YYYY'))</P> <P>or</P> <P>Date(Date#(FILE_REGD_DATE,'OrginalFormat'),'MM/DD/YYYY')</P> Sun, 25 Sep 2022 12:32:08 GMT BrunPierre 2022-09-25T12:32:08Z https://community.qlik.com/t5/App-Development/date-key-issue/m-p/1985005#M81299 <P>I try to map the key from d-date table to the d-patient with common date and I put the same date format for both dates even though the key not mapping . screen shots are attached</P> <P>how to solve the issue????</P> Sun, 25 Sep 2022 06:54:54 GMT https://community.qlik.com/t5/App-Development/date-key-issue/m-p/1985005#M81299 Sam_1985 2022-09-25T06:54:54Z https://community.qlik.com/t5/App-Development/date-key-issue/m-p/1985028#M81301 <P>Maybe FILE_REGD_DATE is not properly formatted in both tables. </P> <P>Try with these</P> <P>&nbsp;Num(Date#(FILE_REGD_DATE, 'MM/DD/YYYY'))</P> <P>or</P> <P>Date(Date#(FILE_REGD_DATE,'OrginalFormat'),'MM/DD/YYYY')</P> Sun, 25 Sep 2022 12:32:08 GMT https://community.qlik.com/t5/App-Development/date-key-issue/m-p/1985028#M81301 BrunPierre 2022-09-25T12:32:08Z