Answer Posted / kalyan dhara

FOR UPDATE and CURRENT OF
---------------
When you issue a SELECT...FOR UPDATE statement, the RDBMS
automatically obtains exclusive row-level locks on all the
rows identified by the SELECT statement, holding the records
“for your changes only” as you move through the rows
retrieved by the cursor. No one else will be able to change
any of these records until you perform a ROLLBACK or a COMMIT.

CURSOR toys_cur IS
SELECT name, manufacturer, preference_level,
sell_at_yardsale_flag
FROM my_sons_collection
WHERE hours_used = 0
FOR UPDATE;

UPDATE table_name
SET set_clause
WHERE CURRENT OF toys_cur ;

OR

DELETE FROM table_name
WHERE CURRENT OF toys_cur ;

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