Transaction Control Language (TCL)
Transaction Control Language (TCL) commands are used to manage transactions within the database.
A transaction is a sequence of one or more SQL operations treated as a single, indivisible unit of work. TCL ensures that either all the operations within the transaction succeed and are saved permanently, or none of them take effect if an error occurs. This is the foundation of data integrity (the “A” for Atomicity in ACID).
Oxibase utilizes a Multi-Version Concurrency Control (MVCC) engine. This means that when you start a transaction, you get a consistent snapshot of the database at that exact moment in time, entirely isolated from the changes other concurrent users might be making.
Core Commands
All transaction control flows are managed through a few key commands, which are fully detailed on the Transaction Control reference page:
BEGIN TRANSACTION: Starts a new isolated transaction block.COMMIT: Successfully concludes the transaction, making all of your data modifications permanently visible to other users.ROLLBACK: Aborts the transaction, undoing all modifications made since theBEGINstatement.SAVEPOINT: Creates a checkpoint within a large transaction, allowing you to partially roll back to a specific state without aborting the entire transaction.