Build fluency in the vocabulary of two-phase locking (2PL).
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1 / 5
A teammate explains that a database transaction acquires all the locks it will need during a growing phase and releases none of them until it enters a shrinking phase where it only releases locks and acquires no new ones, guaranteeing a serializable execution order between concurrent transactions. What is being described?
Two-phase locking (2PL) is exactly what is described here. A DNS zone transfer is an unrelated concept about replicating name server records. Understanding two-phase locking is exactly why it comes up so often in real engineering discussions of this kind of problem.
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During a design review, the team adopts two-phase locking, specifically to gain a concrete benefit. Which capability does this provide?
Two-phase locking here provides a guaranteed serializable execution order between concurrent transactions. Acquiring and releasing locks in an arbitrary order is the alternative this avoids. This behavior is exactly why two-phase locking is favored in this kind of scenario.
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In a code review, a dev notices a system relies on acquiring and releasing locks in whatever order a transaction happens to need them during execution, with no rule preventing a transaction from acquiring a new lock after it has already started releasing others, instead of enforcing two-phase locking. What does this represent?
This is a missed two-phase-locking-opportunity, since enforcing the growing-then-shrinking discipline would guarantee a serializable execution order. A cache eviction policy is an unrelated concept about discarded cache entries. This pattern is exactly the kind of gap a reviewer flags once the tradeoffs are understood.
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An incident report shows two concurrent transactions produced a result inconsistent with any possible serial execution order because the database's locking discipline let a transaction acquire a new lock after it had already begun releasing others, opening a window for an unsafe interleaving. What practice would prevent this?
Enforcing two-phase locking so every transaction fully separates its lock-acquiring phase from its lock-releasing phase. Continuing the prior approach regardless of the risk it has already caused is exactly what led to the incident described here. This fix is the standard remedy once the root cause is confirmed.
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During a PR review, a teammate asks why the team enforces two-phase locking instead of acquiring and releasing locks in an arbitrary order. What is the reasoning?
Two-phase locking trades reduced concurrency for a guaranteed serializable execution order, while releasing locks as soon as possible maximizes concurrency but can no longer guarantee transactions behave as if they ran one at a time. This is exactly why two-phase locking is favored in scenarios that call for it, while the alternative remains acceptable in simpler cases that don't.
What does the "Two-phase locking (2PL) Vocabulary" vocabulary exercise cover?
This exercise tests real IT vocabulary related to two-phase locking (2pl) vocabulary through 5 multiple-choice questions, each built from realistic workplace sentences rather than abstract definitions.
Is this vocabulary exercise free to use?
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How many questions does this exercise have?
This exercise has 5 questions. Each one shows a real-world sentence or scenario with multiple-choice options and an explanation once you answer.
What happens after I answer a question?
You'll see immediate feedback showing whether your answer was correct, along with a short explanation of why — then a button to move to the next question, and a full results screen at the end.
Can I retry the exercise if I get questions wrong?
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Are these vocabulary exercises connected to other topics?
Yes — browse the full vocabulary exercises hub to find related modules covering adjacent IT topics and roles.
How is this different from reading a glossary or blog article?
Exercises like this one are active recall drills — you have to choose the correct term or phrasing yourself, which builds retention faster than passively reading a definition.
Where can I find more vocabulary exercises?
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