title: Proc SQL in SAS and lag and lead
body: <p>I'm struggling a bit with a problem I can't quite get my head around.</p>
  
  <p>Let's say we have a few columns;</p>
  
  <p>IP-address, time stamp, SSN.</p>
  
  <p>How would I go finding occurrences where the same IP appears in several records where the time is within the same one hour window (as an example of a window of time) and there are several SSNs.</p>
  
  <p>This could for example be used for received applications for whatever, where we get a lot of traffic from one location where the data given varies.</p>
  
  <p>Might lag or lead be good?</p>
  
  <p>I'm using SAS, but only Proc SQL really. Might lag or lead be a way to go?</p>
  
  <p>Thank you for the help!</p>