Databases · Middle · Question 65 of 75

What is a 'phantom read'?

1Reading a row that was deleted long ago
✓Correct answer: Re-running a query with the same condition in one transaction returns new rows that another transaction inserted and committed
3A query that returns rows from a different table

Explanation

The SQL standard allows phantoms under Repeatable Read, but PostgreSQL's Repeatable Read uses a snapshot and doesn't show them.

Further reading

PostgreSQL: Transaction isolation ↗

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