1. A method for repairing defective memory cells of a memory device, the method comprising: receiving an access command having an access address and an access operation, the access address including a row address and a column address; determining whether the row address and the column address of the access address are the same as a pre-recorded row address and column address of a defective memory cell; if the row address and the column address of the access address are the same as the respective row and column addresses of the defective memory cell, finding a redundant memory cell associated with the defective memory cell in response to the access address; and executing the access operation using the redundant memory cell.