Patent ID: 8620880

Claim:
A database system comprising: a storage unit that stores a database including an entity data group containing a plurality of entity data and a plurality of identifier tables having only a plurality of fixed-length data; and a data processing unit that receives a query and performs data processing on the database on the basis of the received query, wherein each of the identifier tables includes at least one tuple that is defined in a row direction and at least one attribute field that is defined in a column direction, stores a plurality of data identifiers uniquely indicating the plurality of entity data as the fixed-length data, and has a data structure corresponding to the at least one attribute field into which a tabular data having a plurality of tuples including the plurality of data identifiers according to a plurality of attribute fields is divided, the database further includes a link table that links corresponding tuples between the identifier tables, and includes at least one tuple including data to link the plurality of data identifiers, which are stored in the identifier tables, the plurality of data identifiers is stored in each of the identifier tables sequentially, the data processing unit performs the data processing using the link table and the identifier tables, the database includes a plurality of sub-entity data having content related to the plurality of entity data, the identifier table further includes sub-data identifiers that are in one-to-one correspondence with the data identifiers and uniquely indicate the sub-entity data, and when selecting entity data from the entity data group by searching the identifier table, the data processing unit reads sub-entity data having content related to the selected entity data from the database using the sub-data identifiers.