| 主权项 |
1. A computerized distributed database system comprising:
a main database node server executing, with at least one processor, in a source-database node of a source-database duster, wherein the main database node server manages database server operations, and wherein the main database node server communicates a source-database cluster state and a specified server operation metadata to a data-shipping daemon, wherein the specified server operation metadata comprises an information about server operation occurring, on the source-database node; a data-shipping daemon executing in the source-database node, wherein the data-shipping daemon comprises, and wherein the data-shipping daemon further comprises:
a failure-handling module that resumes an operation of the data-shipping daemon at a substantially current point of the digest log in the event of a recovery of the source-database node from a failed state, and that takes responsibility of shipping of data for other source-database cluster nodes which are not currently present in the source-database cluster, wherein the digest log comprises a ring-buffer,wherein the ring-buffer comprises a most recent specified server operation metadata, and wherein the digest logger overwrites the oldest specified server operation metadata when the ring buffer is full, andwherein the data-shipping daemon further comprises:
an event logger for receiving a database event information from the destination database node over a named pipe and for storing the database event information in an event log;an event processor for reading the event logs and for messaging an event-queue manager to execute the asynchronous database trigger functions, andan event-queue manager or managing an event queue, wherein the event queue, comprises a list of asynchronous database trigger functions, and wherein the event-queue manager calls an asynchronous database trigger function based on an order of the event queue; a digest logger receiving the specified server operation metadata and storing the specified server operation metadata in a digest log, and wherein the data log comprises a file of the specified server operation metadata; and a data shipper module reading the digest log and communicate data referred to in the specified server operation metadata in the digest log to a destination database node in a destination database cluster. |
