https://communities.sas.com/t5/SAS-Studio/joins-in-sql/m-p/543707#M7208 <P>The best proof for uniqueness is a sort with nodupkey. If that does not delete any duplicates, you have unique keys.</P> Sat, 16 Mar 2019 06:25:53 GMT Kurt_Bremser 2019-03-16T06:25:53Z https://communities.sas.com/t5/SAS-Studio/joins-in-sql/m-p/543706#M7207 <P>hello ,</P><P>if i have 2 tables containing product id as unique id , can i say that the left and the right joins of these two tables using product id with distinct&nbsp; ,can i prove that these two have product id as unique id if left and right joins&nbsp; have equal number of records ? .</P> Sat, 16 Mar 2019 04:48:07 GMT https://communities.sas.com/t5/SAS-Studio/joins-in-sql/m-p/543706#M7207 Shrutibhatnagar 2019-03-16T04:48:07Z https://communities.sas.com/t5/SAS-Studio/joins-in-sql/m-p/543707#M7208 <P>The best proof for uniqueness is a sort with nodupkey. If that does not delete any duplicates, you have unique keys.</P> Sat, 16 Mar 2019 06:25:53 GMT https://communities.sas.com/t5/SAS-Studio/joins-in-sql/m-p/543707#M7208 Kurt_Bremser 2019-03-16T06:25:53Z