Device and method for encoding data column

Abstract

A device and a method for encoding a data column are disclosed. A schema inquiry unit inquires into a schema of an original table which is a data table for performing encoding in a database in which a plurality of data tables are stored. A backup performing unit generates schema information of a backup table on the basis of the schema of the original table, generates a backup table by using the schema information of the backup table so as to copy data of the original table into the backup table, changes the original table by adding a backup column to the original table, and inactivates constraint conditions included in the changed original table so as to copy original columns included in the changed original table into the backup column. An encoding unit encodes data of an encoding target column, a column in which encoding is to be performed in the changed original table, and enters the data in each field of the original columns of the changed original table. Then, when the encoding for the data of the encoding target column is completed, the backup performing unit deletes the backup column from the changed original table and activates the constraint conditions.