Hi,
SVDB is a database file getting generated after you run LVS. Which contains the LVS errors and other run details.
There can be two reasons because of that you are getting this error.
1. SVDB path is Incorrect : Verify the path correctly. Make sure the database file generated from your earlier LVS run exist in the LVS run directory. and Point to that location.
2. LVS is not done with RC Extraction Enabled : You need to run LVS with RC_Extraction enabled in LVS Runset. You can check some #define variable that enables RC_Extraction. and set it to true(1).
Thanks,
vlsi123