2025 Query Profiles and Tuning Flashcards
1
Q
What is ‘Percentage scanned from cache’
A
How much data is accessed from the local cache
2
Q
How can you increase the ‘Percentage scanned from cache’
A
In ETL queries, colocate queries that retrieve data from the same tables
3
Q
What is ‘Remote Disk I/O’
A
Time spent on remote I/O, the smaller the better
4
Q
What does it mean if ‘Bytes spilled to remote storage’ is high
A
Warehouse might not be sized properly
5
Q
What is ‘good’ when it comes to ‘Partitions scanned and partitions total’
A
If the partitions scanned are a small fraction of the partitions total, the pruning is efficient
6
Q
What does Search Optimization not support
A
External tables.
Materialized views.
Column concatenation.
Analytical expressions.
Casts on table columns (except for fixed-point numbers cast to strings).
