Snowflake Certification Practice Test

What is the main benefit of defining low cardinality columns in clustering keys?

1. Increases storage costs

2. Improves query performance

3. Reduces data load times

4. Ensures data frequency tracking

The correct answer is: Improves query performance

The main benefit of defining low cardinality columns in clustering keys is that it improves query performance. Low cardinality columns, which have a limited number of distinct values, can significantly enhance the efficiency of data retrieval operations. When a clustering key is based on low cardinality columns, it means that the data is organized in such a way that related records are stored close to one another on disk. This proximity allows Snowflake to minimize the amount of data that needs to be scanned during query execution, leading to faster access times and improved overall performance, especially for queries that filter or aggregate based on those clustering keys. In contrast, options related to increased storage costs or reduced data load times do not align with the fundamental purpose of clustering keys. While clustering can involve maintenance overhead, the focus here is on read performance, not on ensuring data frequency tracking, which does not pertain to the primary advantages that clustering aims to provide.