Maximizing Query Performance: Identifying the Slowest Queries in Your Database

The Challenge:

As your database scales, maintaining optimal performance becomes increasingly challenging.
Identifying and addressing the slowest queries is crucial for enhancing overall efficiency.


Leveraging Firebolt's powerful analytics capabilities allows you to pinpoint and optimize the slowest queries in your database. The provided SQL snippet meticulously analyzes query execution patterns, focusing on successfully ended queries within a specific timeframe, excluding those targeting system information schemas. By grouping these queries based on their normalized hash ("query_text_normalized_hash" in Docs) and filtering out infrequent executions, the query delivers a concise overview of the slowest queries, ranked by their average duration. This targeted approach empowers you to streamline database operations, ensuring high performance and reliability.

Use this query to find the slowest queries in your DB -

SELECT    MAX(start_time) AS last_execution,    COUNT(*) AS number_of_normalized_hash_executions,    ROUND(MIN(duration_usec)/10^6) AS min_duration,    ROUND(AVG(duration_usec)/10^6) AS avg_duration,    ROUND(MEDIAN(duration_usec)/10^6) AS median_duration,    ROUND(MAX(duration_usec)/10^6) AS max_duration,    ANY(query_text) AS sample_queryFROM    information_schema.query_historyWHERE    status = 'ENDED_SUCCESSFULLY'    AND start_time BETWEEN '2024-03-01 00:00:00' AND '2024-04-01 00:00'    AND query_text NOT ILIKE '%information_schema%'GROUP BY    query_text_normalized_hashHAVING    COUNT(*) > 5ORDER BY    avg_duration DESCLIMIT 30;


By identifying and analyzing the slowest queries using this method, you can take targeted actions to optimize them, enhancing the overall performance and efficiency of your database.

This guidance is based on Firebolt's advanced query optimization techniques and is designed to assist in maintaining a high-performance database environment .

Recommended Help Center Articles/DOCS to Improve Performance: