an efficient method for storing relational data in a memory space uses b tree and b + tree structures to store data for a database where non - identical values are stored in a string buffer and pointers to the string buffer are stored in a table buffer , and where identical data is stored only once , and each instance of that value in the database is referenced by a pointer to such identical data corresponding to the locations in the database where that identical value exists , thereby preserving physical memory and increasing the storage capacity of a fixed memory space .