How Data Locks Are Respected

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How Data Locks Are Respected? - Oracle DBA FAQ - Understanding SQL Transaction Management

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A

Here are the rules on how data locks are respected:

All statements ignore data locks owned its own transaction.
SELECT query statements ignores data locks owned by any transactions.
INSERT, UPDATE, and DELETE statements in a READ COMMITTED transaction will wait for data locks on their targeted rows by other transactions to be released.
INSERT, UPDATE, and DELETE statements in a SERIALIZABLE transaction will fail if their targeted rows has data locks owned by other transactions.

2007-04-17, 5287👍, 0💬

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