A computer-implemented method for flexibly storing data in a database so as to allow facile updating and maintenance of the database, including the steps of: (a) providing a first array having rows and columns for storing a first plurality of key entries; (b) arranging the key entries within each of the rows in a monotonic order; (c) providing a second array for storing a second plurality of key entries having rows and at least one column, such that the first and second arrays form a hierarchical structure, wherein the second plurality of entries represents a higher level of the hierarchical structure with respect to the first plurality of entries; (d) identifying an update position for performing a database update operation, and (e) performing the update operation by rearranging a portion of the first plurality of entries.