Techniques perform data input and output. For example, there is provided a technique for updating a data pattern table. The technique involves: during a time period for establishing or updating the data pattern table: receiving a data write request; making statistics of a frequency of data being written; and writing data frequently used and an identification of the data to a corresponding entry of the data pattern table based on a result of the statistics. Using such a technique, a data pattern table can be customized and data storage efficiency can be improved.