Progress
Embedded SQL-92
Guide and Reference
Introduction to Transactions
A transaction is a sequence of operations on a database. Transactions are both atomic and durable. Atomicity refers to the property that either all the operations in a transaction are completed if the transaction is committed, or none of the operations are completed if the transaction is rolled back. Durability refers to the property that once you COMMIT a transaction, the changes made by the transaction are permanent.
Any executable statement is executed as part of a transaction. In an ESQL program, when you execute a statement and there is already an active transaction, the statement executes as part of the existing transaction. If an active transaction does not exist, execution of the SQL statement starts a new transaction. This transaction becomes the active transaction for that ESQL program. All subsequent SQL statements will execute as part of this transaction until the application ends the transaction with an explicit COMMIT or ROLLBACK operation.
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