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  2. Savepoint - Wikipedia

    en.wikipedia.org/wiki/Savepoint

    Issuing the commands ROLLBACK or COMMIT will also discard any savepoints created since the start of the main transaction. Savepoints are defined in the SQL standard and are supported by all established SQL relational databases, including PostgreSQL , Oracle Database , Microsoft SQL Server , MySQL , IBM Db2 , SQLite (since 3.6.8), Firebird , H2 ...

  3. Rollback (data management) - Wikipedia

    en.wikipedia.org/wiki/Rollback_(data_management)

    SQL refers to Structured Query Language, a kind of language used to access, update and manipulate database. In SQL, ROLLBACK is a command that causes all data changes since the last START TRANSACTION or BEGIN to be discarded by the relational database management systems (RDBMS), so that the state of the data is "rolled back" to the way it was before those changes were made.

  4. Database transaction - Wikipedia

    en.wikipedia.org/wiki/Database_transaction

    When the system processes a COMMIT statement, the transaction ends with successful completion. A ROLLBACK statement can also end the transaction, undoing any work performed since BEGIN. If autocommit was disabled with the start of a transaction, autocommit will also be re-enabled with the end of the transaction.

  5. Redo log - Wikipedia

    en.wikipedia.org/wiki/Redo_log

    Oracle must re-do all redo-log transactions that have both a BEGIN and a COMMIT entry (roll forward), and it must undo all transactions that have a BEGIN entry but no COMMIT entry (roll back). [6] (Re-doing a transaction in this context simply means applying the information in the redo log files to the database; the system does not re-run the ...

  6. Commit (data management) - Wikipedia

    en.wikipedia.org/wiki/Commit_(data_management)

    A commit is an act of committing. The record of commits is called the commit log. In terms of transactions, the opposite of commit is to discard the tentative changes of a transaction, a rollback. The transaction, commit and rollback concepts are key to the ACID property of databases. [1]

  7. Compensating transaction - Wikipedia

    en.wikipedia.org/wiki/Compensating_transaction

    For systems without a commit/rollback mechanism available, one can undo a failed transaction with a compensating transaction, which will bring the system back to its initial state. Typically, this is only a workaround which has to be implemented manually and cannot guarantee that the system always ends in a consistent state.

  8. Cursor (databases) - Wikipedia

    en.wikipedia.org/wiki/Cursor_(databases)

    Cursors are usually closed automatically at the end of a transaction, i.e. when a COMMIT or ROLLBACK (or an implicit termination of the transaction) occurs. That behavior can be changed if the cursor is declared using the WITH HOLD clause (the default is WITHOUT HOLD). A holdable cursor is kept open over COMMIT and closed upon ROLLBACK.

  9. Snapshot isolation - Wikipedia

    en.wikipedia.org/wiki/Snapshot_isolation

    In databases, and transaction processing (transaction management), snapshot isolation is a guarantee that all reads made in a transaction will see a consistent snapshot of the database (in practice it reads the last committed values that existed at the time it started), and the transaction itself will successfully commit only if no updates it has made conflict with any concurrent updates made ...