Oracle International Corporation

Goutam Kulkarni

Joydip Kundu

Douglas Andrew Voss

Qinqin Wang

Roger MacNicol

Raymond Guzman

Archie Williams Brown

Anthony Adams

Richard L Frank

A method and system that annotates a redo log to provide information concerning the execution of a procedure at a primary database. The annotations include entry and exit markers that indicate the beginning and the end of the execution along with any arguments passed to the procedure, and whether the execution of the procedure was successful. At the standby database, these markers are used to create a logical transaction associated with the procedure. The operations performed by the procedure are grouped into individual transactions, and these individual transactions are grouped as belonging to the logical transaction. If the execution of the procedure was successful at the primary database, then the individual transactions are discarded, and the logical transaction is applied by executing the procedure at the standby database. If the execution of the procedure failed at the primary database, then the individual transactions and the logical transaction are discarded.

Techniques for the log-based replication of high-level procedures

Techniques for the logical replication of high-level procedures

Techniques for making light-weight checkpoints in logs of streams of transactions and for extending the logs from the checkpoints. The state saved in the light weight checkpoint need only include the state of all transactions that are active at a prior point in the log and are still active at the checkpoint. A log is extended from the checkpoint by processing new transactions in the transaction stream beginning at the prior point to produce the extending log. When the checkpoint is reached, the state saved at the checkpoint is used to continue to produce the extending log. Techniques are further disclosed for selecting points in the stream of transactions at which the checkpoints may be made and for determining the distance between checkpoints. As disclosed, the log in which the checkpoints are used is a logical log made from a physical log produced by a relational database system. The logical log may be used for replication and for data mining.

Techniques for increasing the usefulness of transaction logs

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.

On-demand multi-version denormalized data dictionary to support log-based applications

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.

Communicating data dictionary information of database objects through a redo stream

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).

Growing community of inventors

Nashua, NH, United States of America

Goutam Kulkarni