1. A method for storing and retrieving a relational instance rij by associate aij, the method comprising a. Creating a database by defining a relation R; b. assigning an index i to the relation R making Ri; c. building a database by storing at least one instance Rij of the Ri in a memory; d. assigning the unique associate aij to the j th instance of the relation Ri; e. logically decomposing the j th instance of the relation R into a series of k single domain relations as follows: 
 rij ( d 1, d 2,. .. dk )= rij ( d 1)* rij ( d 2)*. .. rij ( dk ) where dk denotes the domain dk; f. mapping of the at least one relational instance rij into the corresponding unique associate aij as follows: 
 rij(dk)→ijk|dk|→aij where |dk| is a instance value of the domain dk. g. Storing the aij for each rij (dk) in the memory using a key including the ijk |dk|; h. Querying the database Ri for the aij that satisfy specified conditions within and among domains; i. Retrieving the aij for the rij (dk) using the key; j. Performing at least one set operation on the aij retrieved in accord with specified query conditions; k. Collecting the aij satisfying the specified query conditions; l. Responding to the query.