Which row keys are likely to cause a disproportionate number of reads and/or writes on a particular node in a Bigtable cluster (select 2 answers)?

The correct answer is A. A sequential numeric ID B. A timestamp followed by a stock symbol. Explanation/Reference: ...using a timestamp as the first element of a row key can cause a variety of problems. In brief, when a row key for a time series includes a timestamp, all of your writes will target a single node; fill that node; and then move onto the next node in the…

Submitted by tarun92· Mar 30, 2026Designing data processing systems

Question

Which row keys are likely to cause a disproportionate number of reads and/or writes on a particular node in a Bigtable cluster (select 2 answers)?

Options

AA sequential numeric ID
BA timestamp followed by a stock symbol
CA non-sequential numeric ID
DA stock symbol followed by a timestamp

How the community answered

(22 responses)

A
64% (14)
C
9% (2)
D
27% (6)

Explanation

Explanation/Reference: ...using a timestamp as the first element of a row key can cause a variety of problems. In brief, when a row key for a time series includes a timestamp, all of your writes will target a single node; fill that node; and then move onto the next node in the cluster, resulting in hotspotting. Suppose your system assigns a numeric ID to each of your application's users. You might be tempted to use the user's numeric ID as the row key for your table. However, since new users are more likely to be active users, this approach is likely to push most of your traffic to a small number of nodes. [https://cloud.google.com/bigtable/docs/schema-design]

Topics

#Bigtable hotspots#row key design#sequential keys#timestamp antipatterns

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