What happens to the underlying table data when a CLUSTER BY clause is added to a Snowflake table?

What happens to the underlying table data when a CLUSTER BY clause is added to a Snowflake table?
A . Data is hashed by the cluster key to facilitate fast searches for common data values
B . Larger micro-partitions are created for common data values to reduce the number of partitions that must be scanned
C . Smaller micro-partitions are created for common data values to allow for more parallelism
D . Data may be colocated by the cluster key within the micro-partitions to improve pruning performance

View Answer

Answer: D

Explanation:

When a CLUSTER BY clause is added to a Snowflake table, it specifies one or more columns to organize the data within the table’s micro-partitions. This clustering aims to colocate data with similar values in the same or adjacent micro-partitions. By doing so, it enhances the efficiency of query pruning, where the Snowflake query optimizer can skip over irrelevant micro-partitions that do not contain the data relevant to the query, thereby improving performance.

Reference: Snowflake Documentation on Clustering Keys & Clustered Tables1.

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