https://communities.sas.com/t5/SAS-Programming/proc-sql/m-p/282419#M269850 First: please use some descriptive subjects than "proc sql". It would help to distinguish between your inquiries. <BR />Second: what are you up to? Since you have severe more or less basic SQL questions I sugest that you take some formal training first, and then return to the forum more specific coding problems, or at least show the code you tried so far.<BR /> Wed, 06 Jul 2016 13:43:12 GMT LinusH 2016-07-06T13:43:12Z https://communities.sas.com/t5/SAS-Programming/proc-sql/m-p/282399#M269849 <P>hi,</P><P>&nbsp;what should be the code for this &nbsp;question ?</P><P>In the SMB usage data, create another column &nbsp;to identify churners by using product_ID as key variable (check if the key variable is uniqueID &nbsp;in this case ).the list of churners is given in the 'Churners and labels' along with churn month .use LEFT JOIN OR Right Join .</P> Wed, 06 Jul 2016 12:41:59 GMT https://communities.sas.com/t5/SAS-Programming/proc-sql/m-p/282399#M269849 Prateek1 2016-07-06T12:41:59Z https://communities.sas.com/t5/SAS-Programming/proc-sql/m-p/282419#M269850 First: please use some descriptive subjects than "proc sql". It would help to distinguish between your inquiries. <BR />Second: what are you up to? Since you have severe more or less basic SQL questions I sugest that you take some formal training first, and then return to the forum more specific coding problems, or at least show the code you tried so far.<BR /> Wed, 06 Jul 2016 13:43:12 GMT https://communities.sas.com/t5/SAS-Programming/proc-sql/m-p/282419#M269850 LinusH 2016-07-06T13:43:12Z