Super fast aggregations in PostgreSQL 19

Summary

The article discusses a new optimization in PostgreSQL 19 that speeds up aggregations by reordering join and aggregation operations. It explains the traditional approach and contrasts it with the new method, showing performance improvements. The author notes limitations with GROUP BY CUBE functionality.

Key Takeaways

1. While the new optimization offers significant performance gains, it may not fully benefit less frequently used features like GROUP BY CUBE.
2. PostgreSQL 19 introduces an optimization that can significantly speed up aggregations by changing the order of join and aggregation operations.
3. The new optimizer can decide whether to aggregate first and join later, or join first and aggregate later, leading to massive implications for performance.

Statement Breakdown

• Claimed Facts: 70% of statements the article presents as facts
• Opinions: 20% of statements classified as editorial or subjective
• Claims: 10% of statements surfaced for additional reader evaluation

Credibility & Bias Reasoning

Credibility assessment: The article is written by an author from Cybertec PostgreSQL, a company specializing in PostgreSQL services, suggesting expertise. The article focuses on a specific technical improvement in PostgreSQL 19, providing detailed explanations and examples. The claims are specific and testable, enhancing credibility.

Bias assessment: Technical Advancement Advocacy. The article is enthusiastic about a specific feature in PostgreSQL 19, highlighting its benefits and potential performance improvements. While informative, the focus is primarily on promoting the advantages of this new feature. The author's affiliation with a PostgreSQL services company suggests a vested interest in promoting PostgreSQL's capabilities.

Note: This article presents a technical analysis of a specific feature in PostgreSQL 19. While informative, consider the author's affiliation and potential bias towards promoting PostgreSQL.

Credibility flag: Technical Focus

Claimed Facts (7)

• This statement presents a fact about recent changes in PostgreSQL.
• This statement describes a specific change in PostgreSQL 19.
• This statement describes the data structure used in the example.
• This statement describes the goal of the example query.
• This statement refers to the execution plan in older versions of PostgreSQL.
• This statement describes the new method of execution.
• This statement refers to a graph showing performance differences.

Opinions (6)

• This is a positive assessment of the new feature's ease of use.
• This is a rhetorical question leading to a subjective evaluation.
• This is a subjective assessment of the impact of the change.
• This is a subjective conclusion based on the presented data.
• This is an enthusiastic reaction to the performance improvement.
• This is a subjective assessment of the benefits of the new feature.

Claims (5)

• This statement is overly optimistic and lacks specific evidence.
• The claim that it will speed up aggregations for "basically everyone" is an overstatement.
• This is a vague and unsubstantiated claim without specific metrics.
• This is a hypothetical scenario that may not be representative of all cases.
• The term "countless iterations" is vague and lacks specific quantification.

Key Sources

• Hans-Jürgen Schöning — Author
• Cybertec PostgreSQL — Company specializing in PostgreSQL services
• Author — Author