摘要:
A method, system, and computer program product provides a data dictionary that can represent multiple versions of the schema objects, and which provides improved performance, reduced computing costs, and more accurate results in a variety of applications, such as in a database redo log mining system. A method of providing a data dictionary comprises the steps of determining whether information about the data object is present in a denormalized data dictionary history table, and if the information about the data object is not present in the denormalized data dictionary history table, then querying a normalized data dictionary to obtain the information about the data object, including a version identifier of the data object, and storing the version identifier and the obtained information about the data object including the version identifier in the denormalized data dictionary history table.
摘要:
A system, method, and computer program product communicate data dictionary information of database objects through a redo stream in the form of metadata, which provides the association between the internal numbers used by a database schema to identify database objects and the corresponding user-defined names of the database objects, in the redo stream itself, so that the association information may be easily and quickly used in the analysis of the redo stream of the database transactions. A method of communicating data dictionary information of database objects through a redo stream comprises the steps of performing a change to a first database data table, logging redo information representing the change to the first database data table to a redo stream, and logging information relating to internal identifier mapping information associated with the first database data table to the redo stream.
摘要:
The present invention is directed to a method and mechanism for encoding multiple virtual tables into one or more source tables. An aspect of the invention is directed to the access of a virtual table virtual table without requiring separate entries for the virtual table in the meta-data of a database system. Another aspect of the invention is directed to a virtual table that has different column signatures than its underlying source table(s).