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What are transactions in Oracle?
A transaction is a logical, atomic unit of work that contains one or more SQL statements. A transaction groups SQL statements so that they are either all committed, which means they are applied to the database, or all rolled back, which means they are undone from the database.
How do I find Dblink details in Oracle?
Any user can query USER_DB_LINKS to determine which database links are available to that user. Only those with additional privileges can use the ALL_DB_LINKS or DBA_DB_LINKS view.
What is the default transaction mode in Oracle?
READ COMMITTED
READ COMMITTED This is the default transaction isolation.
What is transaction mode?
The Transaction Statement Mode property specifies the action to be taken when a transaction ends. The following actions are possible: Unspecified – Specifies that the default action taken when a transaction ends. Rollback – a transaction is rolled back when it ends. Commit – a transaction is committed when it ends.
Can a transaction be applied to an Oracle Database?
Oracle Database must allow for two situations. If all three SQL statements maintain the accounts in proper balance, then the effects of the transaction can be applied to the database.
What does transaction ID mean in Oracle Database?
A transaction groups SQL statements so that they are either all committed, which means they are applied to the database, or all rolled back, which means they are undone from the database. Oracle Database assigns every transaction a unique identifier called a transaction ID.
What happens when Oracle commits a DML statement?
If the current transaction contains DML statements, then Oracle Database first commits the transaction and then runs and commits the DDL statement as a new, single-statement transaction. A user exits normally from most Oracle Database utilities and tools, causing the current transaction to be implicitly committed.
What happens when a transaction ends in Oracle?
A client process terminates abnormally, causing the transaction to be implicitly rolled back using metadata stored in the transaction table and the undo segment. After one transaction ends, the next executable SQL statement automatically starts the following transaction.