In an

Oracle database Oracle Database (commonly referred to as Oracle DBMS, Oracle Autonomous Database, or simply as Oracle) is a proprietary multi-model database management system produced and marketed by Oracle Corporation. It is a database commonly used for ru ...

, a change vector consists of a single change to a single

data block In computing (specifically data transmission and data storage), a block, sometimes called a physical record, is a sequence of bytes or bits, usually containing some whole number of records, having a fixed length; a ''block size''. Data thus s ...

. A change vector is the smallest unit of change recorded in a

redo log In the Oracle RDBMS environment, redo logs comprise files in a proprietary format which log a history of all changes made to the database. Each redo log file consists of redo records. A redo record, also called a redo entry, holds a group of cha ...

(in its turn, a redo log comprises files in a proprietary format which logs a history of all changes made to the database).

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Change Vector
Oracle software Transaction processing {{database-stub