Apparatus and methods for transferring database objects into and out of database systems

摘要

Techniques for transferring objects between database systems. A transfer is controlled by a master table in the RDBMS that is performing the transfer operation. The master table specifies the kind of transfer operation to be performed, a set of objects to be transferred, operations to be performed on the objects as they are being transferred, and filters for selecting a subset of the objects. During execution of the transfer, the transfer mechanism maintains and updates state in the master table and thereby makes it possible for the entity that is doing the transfer to determine the current status of the transfer and to restart the transfer after it has been stopped. The entity that is performing the transfer may detach from the transfer without stopping the transfer and later again attach to the transfer.