What Is a Data Lock in Oracle

Q

What Is a Data Lock in Oracle?

✍: FYIcenter.com

A

A data lock is logical flag the Oracle server is placed on data objects to give an exclusive right to a transaction. Statements in other transactions needs to respect data locks based on certain rules. Rules on data locks are:

SELECT query statements do not create any data locks.
INSERT, UPDATE, and DELETE statements create data locks on the affected rows.
Data locks are released when the owner transaction ends.

⇒ How Data Locks Are Respected in Oracle

⇐ Supported Transaction Isolation Levels in Oracle

⇑ Understanding SQL Transaction Management in Oracle

⇑⇑ Oracle Database Tutorials

2019-08-19, 2331🔥, 0💬

What Is a Data Lock in Oracle
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Restrictions in a READ ONLY Transaction in Oracle
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How Oracle Handles Dead Locks in Oracle
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Experiments of Data Locks in Oracle
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General Rules on Data Consistency in Oracle
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Supported Transaction Isolation Levels in Oracle
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