Transaction management in a database management system (DBMS) refers to the process of controlling or coordinating the execution and the effects of transactions on a database. Transaction management is used to ensure the integrity, the consistency, and the reliability of the data in a database, and to provide a mechanism for rollback or recovery in case of errors or failures.
A transaction is a unit of work or a logical operation that is performed on a database, and it is usually composed of one or more SQL statements or commands. Transactions are used to manipulate or to modify the data in a database, and to ensure that the changes or the effects of the transaction are either fully executed or fully undone. Transactions are usually implemented using transactions, locks, and isolation levels, and they are usually specified using the BEGIN TRANSACTION, COMMIT TRANSACTION, ROLLBACK TRANSACTION, and SAVEPOINT statements or commands.
Transaction management in a DBMS is used to control or to coordinate the execution and the effects of transactions on a database, and to provide a mechanism for ensuring the integrity, the consistency, and the reliability of the data in a database. Transaction management is usually implemented using the following techniques or technologies:
- Transactions: Transactions are used to enclose one or more SQL statements or commands that need to be executed as a unit of work or a logical operation, and to ensure that the changes or the effects of the transaction are either fully executed or fully undone. Transactions are used to manipulate or to modify the data in a database, and to ensure that the changes or the effects of the transaction are either fully executed or fully undone.
- Locks: Locks are used to control the access or the modification of the data in a database by multiple users or processes, and to ensure that the data is accessed or modified in a consistent or a coherent way. Locks are usually implemented using various types of locks, such as shared locks, exclusive locks, and update locks, and they are used to prevent conflicts or inconsistencies in the access or the modification of the data in a database.
- Isolation levels: Isolation levels are used to specify the level of isolation or the level of concurrency of the data in a database, and to ensure that the changes or the effects of a transaction are isolated or isolated from other transactions. Isolation levels are usually implemented using various levels of isolation, such as read uncommitted, read committed, repeatable read, and serializable, and they are used to control the visibility or the availability of the data in a database to other transactions.
Transaction management in a DBMS is an essential aspect of database management, and it is used to control or to coordinate the execution and the effects of transactions on a database, and to provide a mechanism for ensuring the integrity, the consistency, and the reliability of the data in a database. Transaction management is usually implemented using transactions, locks, and isolation levels, and it is usually specified using the BEGIN TRANSACTION, COMMIT TRANSACTION, ROLLBACK TRANSACTION, and SAVEPOINT statements or commands.