Managing overflow access records in a database

摘要

Overflow access records (OARs) are managed in a database system. An OAR is created in response to receiving an update command for a data record and to the updated data record generated by the update command not fitting onto the page in the table where the data record was stored. The OAR that is created includes an index counter that indicates a number of indexes associated with the table. When an OAR is accessed in response to a query command, an identifier of the accessed OAR is replaced in the index by an identifier of a data record pointed to by the OAR, and the index counter in the accessed OAR is changed by a predefined amount. When the index counter reaches a predefined value, the accessed OAR is removed from the table.