Which pairing of read phenomenon and description is correct?

Problem Statement

Explanation

Phantoms are new or missing rows that match a predicate on a later scan. They show up with range predicates. Non-repeatable reads are the same row showing different values. Dirty reads are uncommitted values. Lost updates happen when both read the same value and the later write overwrites the earlier without awareness.

Code Solution

SolutionRead Only

/* Phantom example */
-- T1: SELECT * FROM orders WHERE amt > 100;  -- sees N
-- T2: INSERT order amt=200 COMMIT
-- T1: re-run: now sees N+1

Practice Sets

This question appears in the following practice sets:

Transactions, Concurrency & Isolation

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Which pairing of read phenomenon and description is correct?

Problem Statement

Explanation

Code Solution

Practice Sets

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Master Interviews Anywhere, Anytime

Which pairing of read phenomenon and description is correct?

Problem Statement

Explanation

Code Solution

Practice Sets

Related Questions

Which SQL statement retrieves all columns and rows from a table named employees?

Which clause filters rows before aggregation and affects which rows are grouped?

What is the default sort order when ORDER BY is used without ASC or DESC?

Which construct is commonly used to paginate results in SQL engines like Postgres and MySQL?

Which predicate correctly checks for missing values in standard SQL?

More from SQL & Databases

Master Interviews
Anywhere, Anytime