General Rules on Data Consistency in Oracle

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What Are the General Rules on Data Consistency in Oracle?

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A

Here is a list of general rules on data consistency:

All SQL statements always work with a snapshot of the database to provide data consistency.
For READ WRITE transactions, the snapshot is taken when each statement starts.
For READ ONLY transactions, the snapshot is taken when the transaction starts.
The snapshot never include uncommitted changes from other transactions.
The snapshot always include uncommitted changes from its own transaction.

⇒ Supported Transaction Isolation Levels in Oracle

⇐ Restrictions in a READ ONLY Transaction in Oracle

⇑ Understanding SQL Transaction Management in Oracle

⇑⇑ Oracle Database Tutorials

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