https://communities.sas.com/t5/SAS-Procedures/Proc-Sort/m-p/59344#M16743 The WHERE statement you have coded references a value-constant which is a SAS DATE -- the suffix "d" indicates so. Here is some SAS documentation reference:<BR /> <BR /> <A href="http://support.sas.com/documentation/cdl/en/lrcon/61722/HTML/default/a000780334.htm" target="_blank">http://support.sas.com/documentation/cdl/en/lrcon/61722/HTML/default/a000780334.htm</A><BR /> <BR /> <A href="http://support.sas.com/documentation/cdl/en/lrcon/61722/HTML/default/a002200738.htm" target="_blank">http://support.sas.com/documentation/cdl/en/lrcon/61722/HTML/default/a002200738.htm</A><BR /> <BR /> <BR /> Scott Barry<BR /> SBBWorks, Inc.<BR /> <BR /> Google advanced search argument, this topic/post:<BR /> <BR /> using date constants site:sas.com Thu, 18 Feb 2010 13:39:38 GMT sbb 2010-02-18T13:39:38Z https://communities.sas.com/t5/SAS-Procedures/Proc-Sort/m-p/59343#M16742 Hello ,<BR /> <BR /> could you please guide me in the interpretation of the proc sort command and the Date = '15dec1999'd command in :<BR /> <BR /> <BR /> proc sort data = sc.target121999 out = sortb;<BR /> by FlightID;<BR /> where Date = '15dec1999'd AND Origin = 'BHM';<BR /> run;<BR /> <BR /> proc print data=sortb; <BR /> run;<BR /> <BR /> <BR /> <BR /> kind regards ,<BR /> markC Thu, 18 Feb 2010 12:58:08 GMT https://communities.sas.com/t5/SAS-Procedures/Proc-Sort/m-p/59343#M16742 deleted_user 2010-02-18T12:58:08Z https://communities.sas.com/t5/SAS-Procedures/Proc-Sort/m-p/59344#M16743 The WHERE statement you have coded references a value-constant which is a SAS DATE -- the suffix "d" indicates so. Here is some SAS documentation reference:<BR /> <BR /> <A href="http://support.sas.com/documentation/cdl/en/lrcon/61722/HTML/default/a000780334.htm" target="_blank">http://support.sas.com/documentation/cdl/en/lrcon/61722/HTML/default/a000780334.htm</A><BR /> <BR /> <A href="http://support.sas.com/documentation/cdl/en/lrcon/61722/HTML/default/a002200738.htm" target="_blank">http://support.sas.com/documentation/cdl/en/lrcon/61722/HTML/default/a002200738.htm</A><BR /> <BR /> <BR /> Scott Barry<BR /> SBBWorks, Inc.<BR /> <BR /> Google advanced search argument, this topic/post:<BR /> <BR /> using date constants site:sas.com Thu, 18 Feb 2010 13:39:38 GMT https://communities.sas.com/t5/SAS-Procedures/Proc-Sort/m-p/59344#M16743 sbb 2010-02-18T13:39:38Z