Answer-first summary for fast verification
Answer: Pruning is not being performed efficiently.
The Query Profile showing all partitions being scanned indicates inefficient pruning, which is the most likely cause of the performance issue. Pruning in Snowflake allows the query engine to skip micro-partitions that don't contain relevant data for the query, significantly reducing the amount of data scanned. When all partitions are scanned, it means pruning isn't working effectively, leading to unnecessary data processing. While option C (incorrect joins) could potentially cause performance issues, the specific symptom of 'all partitions being scanned' directly points to pruning inefficiency. The community discussion strongly supports option A with 100% consensus and upvoted comments explaining that pruning reduces the number of micro-partitions scanned, improving query response time.
Author: LeetQuiz Editorial Team
Ultimate access to all questions.
A complex SQL query joining eight tables is experiencing slow performance. The Query Profile indicates that all partitions are being scanned.
What is the most likely cause of this performance issue?
A
Pruning is not being performed efficiently.
B
A huge volume of data is being fetched, with many joins applied.
C
Incorrect joins are being used, leading to scanning and pulling too many records.
D
The columns in the micro-partitions need granular ordering based on the dataset.
No comments yet.