December 2002
Intermediate to advanced
928 pages
85h 29m
English
The first block of each datafile is called the datafile header. It contains critical information used to maintain the overall integrity of the database. One of the most crucial pieces of information in this header is the checkpoint structure, a logical timestamp that indicates the last point at which changes were written to the datafile. This timestamp is critical for recovery situations. The Oracle recovery process uses the timestamp in the header of a datafile to determine which redo logs to apply to bring the datafile up to the current point in time.