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Ending Transactions
A good quality programming practice is to commit or roll back every transaction explicitly. Whether you rollback or issue the commit in your PL/SQL program or in the host atmosphere, it depends on the flow of application logic. When you neglect to commit or roll back a transaction explicitly, the host atmosphere determines its last state.
For illustration, in the SQL Plus atmosphere, if your PL/SQL block does not involve a COMMIT or ROLLBACK statement, the final state of your transaction totally depends on what you do after running the block. When you execute the data control, data definition, or COMMIT statement or if you issue the DISCONNECT, EXIT, or QUIT command, the Oracle commits the transaction. When you execute a ROLLBACK statement or abandon the SQL Plus session, the Oracle rolls back the transaction.
In the Oracle Pre-compiler atmosphere, if your program does not expire in general, the Oracle rolls back your transaction. The program terminates generally if it explicitly commits or rolls back work and disconnects from the Oracle using the RELEASE parameter, which is as shown:
EXEC SQL COMMIT WORK RELEASE;
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