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Question 12: What is PRAGMA AUTONOMOUS_TRANSACTION?

You are running a pl/sql block or procedure called parent

In that procedure you called another one procedure namely child and that procedure contains commit statement.

After calling the child procedure the transactions done in parent procedure are also committed due to the child procedure commit statement.

But you want to rollback or commit the parent procedure whole transactions based on your requirement after the calling procedure child.

In this situation, you should add the "pragma autonomus transaction" in child procedure.
If you add this statement then it acts as a separate. If you use commit in child procedure it will not affect the parent procedure.

Example :
CREATE OR REPLACE PROCEDURE parent()
AS
BEGIN
UPDATE tab1 SET fieldname = value WHERE condition;
UPDATE tab2 SET fieldname = value WHERE condition;
child();
UPDATE tab4 SET fieldname = value WHERE condition;
IF parentcondition
COMMIT;
ELSE
ROLLBACK;
END IF;
END.

CREATE OR REPLACE PROCEDURE child()
AS
PRAGMA AUTONOMOUS_TRANSACTION;
BEGIN
UPDATE tab3 SET fieldname = value WHERE condition;
COMMIT;
END.


In above case tab1, tab2 and tab4 tables transactions will commit or rollback based on the parentcondition. but tab3 updation will always commits, that is not consider the parent procedure.

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