May 2018
Intermediate to advanced
576 pages
30h 25m
English
Recovery works by applying individual WAL records. These correspond to individual block changes, so there are many WAL records for each transaction. The final part of any successful transaction is a commit WAL record, though there are abort records as well. Each transaction completion record has a timestamp that allows us to decide whether or not to stop at that point.
You can also define a recovery target using a transaction ID (xid), though finding out which xid to use is somewhat difficult, and you may need to refer to external records, if they exist.
Another practical way, which rarely applies after an unexpected disaster, is to define a recovery target with a label, formally known as a named restore point. A restore point ...