Patent ID: 9483517
Filing Date: 2016-11-01
CPC Classification: G06F

Claim Text:
1. A method comprising: maintaining, on persistent storage, a database that is accessible to a database server; wherein the database includes a first set of data; maintaining a second set of data in volatile memory that is accessible to the database server; wherein each data item in the second set of data is a copy of a corresponding data item in the first set of data; wherein both the first set of data and the second set of data have copies of a particular data item; maintaining a bitmap that indicates which data items, in the second set of data, are not currently valid; wherein the maintaining the bitmap includes responding to an update of the particular data item by: after setting the particular bit in the bitmap, receiving, by the database server, a request to execute a database command that requires the particular data item; during execution of the database command: