A method for repairing of the invention includes steps as follows: storing redundant information including an address of the bad column, identification information for identifying a failure in which one of an even column or an odd column of the bad column and an address of a redundant column of a redundant memory region for repairing the bad column; determining whether a column address of a selected column is consistent with the address of the bad column based on the redundant information; when consistent, converting a column of the bad column having the failure into a column of the redundant column based on the identification information; and not converting another column of the bad column without the failure into another column of the redundant column.