A method for use in a flash memory to handle host write commands includes: performing a dummy pattern detection while programing data into a specific section of a first block or a first super block of the flash memory; setting a dummy pattern indicator if all the data that is programmed to the specific section of the first block or the first super block of the flash memory corresponds to a predetermined dummy pattern; and in response to host write commands, modifying a host-to-flash (H2F) address mapping table regarding data that is requested by the host write commands to be programmed to a second block or a second super block of the flash memory without programming the data into the second super block or the second block to complete the host write commands if the dummy pattern indicator is set.