Mastering clustered tables in Event-based streaming

Clustered tables stand as a fundamental element in optimizing data processing within Google BigQuery, playing a pivotal role in enhancing query performance and cost efficiency specifically when querying OWOX BI's Event-based Streaming data. This article serves as a comprehensive guide to unravel the intricacies of clustered tables, addressing key questions to empower users with a nuanced understanding.

What are clustered tables in Google BigQuery?

Clustered tables represent a sophisticated feature within BigQuery, enabling users to define a column sort order using clustered columns. This mechanism significantly enhances query performance and cost-effectiveness. By sorting storage blocks based on clustered columns, queries can scan only relevant blocks, reducing the need to scan the entire table or table partition. For a deeper dive, you can just read the official documentation.

What is the clustering field for the 'events_intraday_YYYYMMDD' table?

The clustering is configured based on the event_name field.

From what date are clustered tables 'events_intraday_YYYYMMDD' created?

As of November 1, 2023, all 'events_intraday_YYYYMMDD' tables are automatically created with clustering.

Do tables created before November 1, 2023, have clustering based on the 'event_name' field?

No, tables created before this date do not have clustering. The new functionality does not impact previously created tables and their data.

Can I query data from both clustered and non-clustered tables in a single SQL query?

Yes, it's possible. However, the true benefits of clustered tables are realized when queries exclusively use clustered tables.

Can the clustering field be changed for the 'events_intraday_YYYYMMDD' tables?

Absolutely. For any customisation in your Event-based Streaming, reach out to our support team at

Do Transformation templates utilize queries to 'events_intraday_YYYYMMDD' tables that already have clustering?

All Transformation templates utilizing data from 'events_intraday_YYYYMMDD' tables function seamlessly. No adjustments are needed in the template code.

Is there a reduction in storage space for clustered tables in BigQuery?

No, the act of clustering itself does not affect the overall size of the tables. However, clustering is instrumental in optimizing data processing costs within clustered tables, assuming that queries are composed accurately.

How to write queries for clustered tables?

Explore examples and best practices for querying clustered tables in the official BigQuery documentation.



Was this article helpful?
0 out of 0 found this helpful
Have more questions? Submit a request


Please sign in to leave a comment.