IPA IP 2024 Question 74

A question IPA Japan published in 令和6年度 ITパスポート試験公開問題問74, translated into English. ITPEC is based on the same exams.

Same question on ITPEC: Apr 2025 Q29

Which of the following is the appropriate description concerning transaction processing?

a)Commit is the reversion of a database to the status prior to the start of the transaction when a transaction is not processed successfully.b)Exclusive control is the confirmation of the content of a database when a transaction is processed successfully.c)Rollback ensures that there are no inconsistencies in data when multiple transactions attempt to update data simultaneously.d)Log is a file that records transaction history of a database.

Explanation

A log records the transaction history of a database — the only description that matches its term.

The log (journal) records each update a transaction makes, with the values before it (before-image) and after it (after-image), and when each transaction commits. After a failure the DBMS uses it to recover: before-images to undo unfinished transactions (rollback), after-images to reapply committed ones to a backup (roll-forward).

Answer (d)

Why not others:

•(a) — returning the database to its state before an unsuccessful transaction is rollback; commit makes a successful transaction's updates permanent
•(b) — confirming the updates of a successful transaction is commit; exclusive control is locking
•(c) — preventing inconsistencies when several transactions update the same data at once is exclusive control (locking), not rollback

Key rule: Commit confirms, rollback undoes, locking keeps concurrent updates from clashing, and the log is what makes both rollback and roll-forward possible.

Databases · AI-written, may contain errors

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This question comes from the past questions IPA Japan publishes, translated into English by ITPEC Practice. ITPEC Practice is an independent study tool and is not affiliated with IPA or ITPEC. See the original paper (PDF) or Report an issue.