12 Data Modeling questions from the Firebase bank, written for Indian campus drives and tech interviews. Every question has a verified answer and an AI-tutor explanation on placd.
Free to start: the 2-minute IT readiness check — six questions and a result.
A.a search that spans every subcollection sharing the same name across the whole database, regardless of parent
B.the throughput problem caused by monotonically increasing keys or sequential timestamps concentrating writes on one storage range
C.the hard ceiling of about one megabyte per record, which pushes large or growing lists into subcollections
D.duplicating data across documents to avoid joins, trading storage and write complexity for fast single-read access
Answer + AI explanation with Pro
2. Which term means: "duplicating data across documents to avoid joins, trading storage and write complexity for fast single-read access"?
Junior
A.Hotspotting
B.Collection group query
C.Document size limit
D.Denormalization
Answer + AI explanation with Pro
3. Which statement is correct?
Junior
A.Denormalization — a search that spans every subcollection sharing the same name across the whole database, regardless of parent
B.Denormalization — the throughput problem caused by monotonically increasing keys or sequential timestamps concentrating writes on one storage range
C.Denormalization — the hard ceiling of about one megabyte per record, which pushes large or growing lists into subcollections
D.Denormalization — duplicating data across documents to avoid joins, trading storage and write complexity for fast single-read access
Answer + AI explanation with Pro
4. What is Document size limit?
Mid
A.the hard ceiling of about one megabyte per record, which pushes large or growing lists into subcollections
B.duplicating data across documents to avoid joins, trading storage and write complexity for fast single-read access
C.a search that spans every subcollection sharing the same name across the whole database, regardless of parent
D.the throughput problem caused by monotonically increasing keys or sequential timestamps concentrating writes on one storage range
Answer + AI explanation with Pro
5. Which term means: "the hard ceiling of about one megabyte per record, which pushes large or growing lists into subcollections"?
Mid
A.Denormalization
B.Hotspotting
C.Document size limit
D.Collection group query
Answer + AI explanation with Pro
6. Which statement is correct?
Mid
A.Document size limit — the hard ceiling of about one megabyte per record, which pushes large or growing lists into subcollections
B.Document size limit — a search that spans every subcollection sharing the same name across the whole database, regardless of parent
C.Document size limit — duplicating data across documents to avoid joins, trading storage and write complexity for fast single-read access
D.Document size limit — the throughput problem caused by monotonically increasing keys or sequential timestamps concentrating writes on one storage range
Answer + AI explanation with Pro
7. What is Collection group query?
Mid
A.a search that spans every subcollection sharing the same name across the whole database, regardless of parent
B.the hard ceiling of about one megabyte per record, which pushes large or growing lists into subcollections
C.duplicating data across documents to avoid joins, trading storage and write complexity for fast single-read access
D.the throughput problem caused by monotonically increasing keys or sequential timestamps concentrating writes on one storage range
Answer + AI explanation with Pro
8. Which term means: "a search that spans every subcollection sharing the same name across the whole database, regardless of parent"?
Mid
A.Hotspotting
B.Denormalization
C.Collection group query
D.Document size limit
Answer + AI explanation with Pro
9. Which statement is correct?
Mid
A.Collection group query — a search that spans every subcollection sharing the same name across the whole database, regardless of parent
B.Collection group query — the throughput problem caused by monotonically increasing keys or sequential timestamps concentrating writes on one storage range
C.Collection group query — the hard ceiling of about one megabyte per record, which pushes large or growing lists into subcollections
D.Collection group query — duplicating data across documents to avoid joins, trading storage and write complexity for fast single-read access
Answer + AI explanation with Pro
10. What is Hotspotting?
Senior
A.the hard ceiling of about one megabyte per record, which pushes large or growing lists into subcollections
B.the throughput problem caused by monotonically increasing keys or sequential timestamps concentrating writes on one storage range
C.a search that spans every subcollection sharing the same name across the whole database, regardless of parent
D.duplicating data across documents to avoid joins, trading storage and write complexity for fast single-read access
Answer + AI explanation with Pro
11. Which term means: "the throughput problem caused by monotonically increasing keys or sequential timestamps concentrating writes on one storage range"?
Senior
A.Collection group query
B.Denormalization
C.Document size limit
D.Hotspotting
Answer + AI explanation with Pro
12. Which statement is correct?
Senior
A.Hotspotting — the throughput problem caused by monotonically increasing keys or sequential timestamps concentrating writes on one storage range
B.Hotspotting — the hard ceiling of about one megabyte per record, which pushes large or growing lists into subcollections
C.Hotspotting — duplicating data across documents to avoid joins, trading storage and write complexity for fast single-read access
D.Hotspotting — a search that spans every subcollection sharing the same name across the whole database, regardless of parent
Answer + AI explanation with Pro
Free to start
Start with a free readiness check
Sign up free for the 2-minute IT readiness check and a scored result. Answers, explanations and the AI tutor on every Data Modeling question come with Pro.