If I populated table1 & table2 with many rows (10 million or above) and then delete all rows (be sure to make DELETE not TRUNCATE) and make TRUNCATE on TABLE2 then response time will be different even both tables contains no data. For TABLE1 all empty blocks must be read, while TABLE2 contains only 1 block to read.
I need to use delete statement with where clause. In this case I cannot user truncate than how can I remove the blocks for table1 to improve the performance?