15 Invalidation questions from the Caching bank, written for Indian campus drives and tech interviews. Every question has a verified answer and an AI-tutor explanation on placd.
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A.serving a slightly outdated copy immediately while asynchronously fetching a fresh version in the background
B.relying on an expiry duration to mark an entry stale rather than actively removing it on data change
C.removing or refreshing the relevant entry as part of the operation that mutates the source record
D.the famous Phil Karlton joke that the hardest problems in computer science are naming things, off-by-one errors, and keeping stored copies fresh
Answer + AI explanation with Pro
2. Which term means: "relying on an expiry duration to mark an entry stale rather than actively removing it on data change"?
Junior
A.Write invalidation
B.Time-based invalidation
C.Explicit invalidation
D.The two hard things quote
Answer + AI explanation with Pro
3. Which statement is correct?
Junior
A.Time-based invalidation — serving a slightly outdated copy immediately while asynchronously fetching a fresh version in the background
B.Time-based invalidation — relying on an expiry duration to mark an entry stale rather than actively removing it on data change
C.Time-based invalidation — removing or refreshing the relevant entry as part of the operation that mutates the source record
D.Time-based invalidation — deliberately deleting or marking a specific entry when the underlying data is known to have changed
Answer + AI explanation with Pro
4. What is Explicit invalidation?
Mid
A.removing or refreshing the relevant entry as part of the operation that mutates the source record
B.the famous Phil Karlton joke that the hardest problems in computer science are naming things, off-by-one errors, and keeping stored copies fresh
C.relying on an expiry duration to mark an entry stale rather than actively removing it on data change
D.deliberately deleting or marking a specific entry when the underlying data is known to have changed
Answer + AI explanation with Pro
5. Which term means: "deliberately deleting or marking a specific entry when the underlying data is known to have changed"?
Mid
A.The two hard things quote
B.Stale-while-revalidate
C.Time-based invalidation
D.Explicit invalidation
Answer + AI explanation with Pro
6. Which statement is correct?
Mid
A.Explicit invalidation — relying on an expiry duration to mark an entry stale rather than actively removing it on data change
B.Explicit invalidation — deliberately deleting or marking a specific entry when the underlying data is known to have changed
C.Explicit invalidation — serving a slightly outdated copy immediately while asynchronously fetching a fresh version in the background
D.Explicit invalidation — removing or refreshing the relevant entry as part of the operation that mutates the source record
Answer + AI explanation with Pro
7. What is Write invalidation?
Mid
A.deliberately deleting or marking a specific entry when the underlying data is known to have changed
B.removing or refreshing the relevant entry as part of the operation that mutates the source record
C.the famous Phil Karlton joke that the hardest problems in computer science are naming things, off-by-one errors, and keeping stored copies fresh
D.serving a slightly outdated copy immediately while asynchronously fetching a fresh version in the background
Answer + AI explanation with Pro
8. Which term means: "removing or refreshing the relevant entry as part of the operation that mutates the source record"?
Mid
A.Time-based invalidation
B.Write invalidation
C.Explicit invalidation
D.Stale-while-revalidate
Answer + AI explanation with Pro
9. Which statement is correct?
Mid
A.Write invalidation — relying on an expiry duration to mark an entry stale rather than actively removing it on data change
B.Write invalidation — removing or refreshing the relevant entry as part of the operation that mutates the source record
C.Write invalidation — serving a slightly outdated copy immediately while asynchronously fetching a fresh version in the background
D.Write invalidation — deliberately deleting or marking a specific entry when the underlying data is known to have changed
Answer + AI explanation with Pro
10. What is The two hard things quote?
Senior
A.serving a slightly outdated copy immediately while asynchronously fetching a fresh version in the background
B.the famous Phil Karlton joke that the hardest problems in computer science are naming things, off-by-one errors, and keeping stored copies fresh
C.removing or refreshing the relevant entry as part of the operation that mutates the source record
D.relying on an expiry duration to mark an entry stale rather than actively removing it on data change
Answer + AI explanation with Pro
11. Which term means: "the famous Phil Karlton joke that the hardest problems in computer science are naming things, off-by-one errors, and keeping stored copies fresh"?
Senior
A.Time-based invalidation
B.Stale-while-revalidate
C.Write invalidation
D.The two hard things quote
Answer + AI explanation with Pro
12. Which statement is correct?
Senior
A.The two hard things quote — deliberately deleting or marking a specific entry when the underlying data is known to have changed
B.The two hard things quote — the famous Phil Karlton joke that the hardest problems in computer science are naming things, off-by-one errors, and keeping stored copies fresh
C.The two hard things quote — relying on an expiry duration to mark an entry stale rather than actively removing it on data change
D.The two hard things quote — serving a slightly outdated copy immediately while asynchronously fetching a fresh version in the background
Answer + AI explanation with Pro
13. What is Stale-while-revalidate?
Mid
A.relying on an expiry duration to mark an entry stale rather than actively removing it on data change
B.removing or refreshing the relevant entry as part of the operation that mutates the source record
C.serving a slightly outdated copy immediately while asynchronously fetching a fresh version in the background
D.deliberately deleting or marking a specific entry when the underlying data is known to have changed
Answer + AI explanation with Pro
14. Which term means: "serving a slightly outdated copy immediately while asynchronously fetching a fresh version in the background"?
Mid
A.Explicit invalidation
B.Write invalidation
C.Stale-while-revalidate
D.Time-based invalidation
Answer + AI explanation with Pro
15. Which statement is correct?
Mid
A.Stale-while-revalidate — deliberately deleting or marking a specific entry when the underlying data is known to have changed
B.Stale-while-revalidate — removing or refreshing the relevant entry as part of the operation that mutates the source record
C.Stale-while-revalidate — serving a slightly outdated copy immediately while asynchronously fetching a fresh version in the background
D.Stale-while-revalidate — relying on an expiry duration to mark an entry stale rather than actively removing it on data change
Answer + AI explanation with Pro
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