PostgreSQL random_page_cost Parameter Examined for Better Query Planning

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A technical blog post by Tomas Vondra explores the PostgreSQL configuration parameter random_page_cost and its impact on query optimization. The parameter influences how the PostgreSQL query planner estimates the cost of random disk page reads relative to sequential reads. Misconfigured values can lead the planner to make suboptimal choices, such as preferring sequential scans over index scans. The post builds on earlier discussions about how modern storage hardware, including SSDs, has changed the relevance of this setting. Developers and database administrators are encouraged to revisit their random_page_cost settings to better reflect their actual storage characteristics.

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