In Oracle Database 12c, when does a transaction begin?
A.
when a transaction ID is allocated for it.
B.
when a user explicitly issues a “begin” statement
C.
when a transaction is assigned to an available undo data segment to record undo entries for
the new transaction
D.
when the first executable SQL statement is encountered
D
D
https://docs.oracle.com/database/121/CNCPT/transact.htm#CNCPT038
Beginning of a Transaction
A transaction begins when the first executable SQL statement is encountered. An executable SQL statement is a SQL statement that generates calls to a database instance, including DML and DDL statements and the SET TRANSACTION statement.