Question

If I have a table with huge amount of data…and If I do incremental delete instead “one time delete”..what’s the benefit ?

Onetime delete

 DELETE table_1
     WHERE BID = @BID
    AND CN = @CN        
     AND PD = @PD;  

Incremental Delete

While (1=1)
Begin
 DELETE TOP (100000) FROM table_1
     WHERE BID = @BID
    AND CN = @CN        
     AND PD = @PD;  

If @@rowcount = 0   -- No row affected.
  BREAK
 ELSE
  Continue
End

I got help from
Deleting data in a sql server table takes much time

Answer 1

Depends on the configuration, I have seen large deletes blow up the transaction log and cause a failure in not enough disk space.

You could also avoid locking escalation by using a smaller batch.