We are collection every user click as follows in a log file
Current Url -------------- Refer Url ------- User ---- Timestamp
/B /A usr1 1/1/2016 : ...
/C /B usr1 ....
/D /C Usr1 .....
/F NULL usr2 .....
What is the best way to construct user click path?
How to do that in SQL or Do I have to write a custom program?