Oracle Corporation
FUNCTION-BASED INDEXES IN DATABASE SYSTEMS

Abstract:

A database system provided according to an aspect of the present disclosure provides indexed data for non-deterministic functions. In an embodiment, a request to maintain an indexed data for a non-deterministic function is received. The non-deterministic function specifies a set of input variables and a set of output variables and a manner in which respective output values are generated for the set of output variables based on corresponding input values for the input variables. Generating output values entails performing operations defined based on a set of data classes in the database system. An indexed data is formed, indicating corresponding output values for respective set of input values present in the set of data classes in the database system. The indexed data is updated when a change to data elements of a first data class of the set of data classes is processed.