Alleviation of Index Hot Spots in Datasharing Environment with Remote Update and Provisional Keys

摘要

In a remote index operation, a first system in a datasharing group performs an operation on a data object in a database, determines a second system in the datasharing group has exclusive access to an index page to be updated according to the operation, and sends to the second system a remote request to change the index page according to the operation. In response, the second system changes the index page with an index entry referencing the data object and marks a key in the index entry as a provisional key. When a third system in the datasharing group reads the index entry, it determines that the key in the index entry is the provisional key. In response, the third system determines whether the data object exists in the database and a committed state of the transaction, and accordingly determines a current state of the data object.

主权项

1. A method for remote index operations in a datasharing system, comprising:
performing an operation on a data object in a database by a first computer system of a plurality of computer systems in a datasharing group, wherein the plurality of computer systems share a storage storing the database, wherein the plurality of computer systems does not share memory or logs; determining, by the first computer system, that a second system of the plurality of computer systems in the datasharing group currently has exclusive access to an index page to be updated according to the operation; sending, by the first computer system to the second computer system, a remote request to change the index page according to the operation; in response to the remote request, changing, by the second computer system, the index page with an index entry referencing the data object; and marking, by the second computer system, a key in the index entry as a provisional key.