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, 2782🔥, 0💬

What Is a Data Lock in Oracle
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How Oracle Handles Dead Locks in Oracle
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Set a READ ONLY Transaction in Oracle
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Restrictions in a READ ONLY Transaction in Oracle
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Experiments of Data Locks in Oracle
How To Experiment a Data Lock in Oracle? If you want to have some experience with data locks, you can create two windows running two SQL*Plus sessions. In session 1, you can run a UPDATE statements to create a data lock. Before committing session 2, switch to session 2, and run a UPDATE statements o... 2019-08-08, 2655🔥, 0💬

Show Existing Locks on the Database in Oracle
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Supported Transaction Isolation Levels in Oracle
What Are Transaction Isolation Levels Supported by Oracle in Oracle? Oracle supports two transaction isolation levels: READ COMMITTED (the default option). If the transaction contains DML that requires row locks held by another transaction, then the DML statement waits until the row locks are releas... 2019-08-19, 2614🔥, 0💬

General Rules on Data Consistency in Oracle
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What Is a Dead Lock in Oracle
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