March 2022
Intermediate to advanced
682 pages
22h 58m
English
All Oracle transactions obey the ACID properties described in Section 11.1. Oracle uses a combination of locking and multiversion timestamping for concurrency control. Read-only transactions never use locks because Oracle keeps multiple versions of data items for read consistency; however, locks are required for write transactions.
A transaction in Oracle consists of one or more DML statements that form a unit of work, or a single data definition language (DDL) statement. Every transaction must have a beginning and an end point. A transaction begins with the first executable SQL statement, or a SET TRANSACTION command, a statement a programmer can use to delimit a transaction and ...