--- title: All Your GUCs in a Row: enable_seqscan | daily.dev description: enable_seqscan = off does not disable sequential scans in PostgreSQL — it only penalizes them so the planner avoids them when alternatives exist. If no usable... canonical: https://daily.dev/posts/all-your-gucs-in-a-row-enable-seqscan-ope0ha3wx twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: All Your GUCs in a Row: enable_seqscan | daily.dev og:description: enable_seqscan = off does not disable sequential scans in PostgreSQL — it only penalizes them so the planner avoids them when alternatives exist. If no usable... og:url: https://daily.dev/posts/all-your-gucs-in-a-row-enable-seqscan-ope0ha3wx og:image: https://api.daily.dev/og/posts/ope0ha3wx.png og:image:alt: All Your GUCs in a Row: enable_seqscan og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # All Your GUCs in a Row: enable_seqscan **[Planet PostgreSQL](https://daily.dev/sources/planet-postgresql)** · 4 min read · 0 upvotes · 0 comments ## Summary enable_seqscan = off does not disable sequential scans in PostgreSQL — it only penalizes them so the planner avoids them when alternatives exist. If no usable index exists for a query, the planner will still choose a sequential scan, now labelled 'Disabled: true' in PostgreSQL 18's EXPLAIN output. The real fix for unwanted sequential scans lies upstream: correcting effective_cache_size, setting random_page_cost to reflect SSD/NVMe storage (~1.1 instead of 4.0), and running ANALYZE to fix stale statistics. enable_seqscan = off is a diagnostic probe to be used per-session, never in postgresql.conf, where it would cause small-table scans to wastefully use indexes instead. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [All Your GUCs in a Row: enable\_indexscan and enable\_bitmapscan](https://daily.dev/posts/all-your-gucs-in-a-row-enable-indexscan-and-enable-bitmapscan-cifajzmnh) · Planet PostgreSQL · 0 upvotes · 0 comments - [All Your GUCs in a Row: enable\_hashjoin](https://daily.dev/posts/all-your-gucs-in-a-row-enable-hashjoin-wdnjt9mms) · Planet PostgreSQL · 0 upvotes · 0 comments - [All Your GUCs in a Row: enable\_indexonlyscan](https://daily.dev/posts/all-your-gucs-in-a-row-enable-indexonlyscan-s3vvm0cff) · Planet PostgreSQL · 0 upvotes · 0 comments --- Tags: [#postgresql](https://daily.dev/tags/postgresql) [View this post on daily.dev](https://daily.dev/posts/all-your-gucs-in-a-row-enable-seqscan-ope0ha3wx) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"All Your GUCs in a Row: enable_seqscan","url":"https://daily.dev/posts/all-your-gucs-in-a-row-enable-seqscan-ope0ha3wx","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/all-your-gucs-in-a-row-enable-seqscan-ope0ha3wx"},"datePublished":"2026-07-11T01:18:07.696Z","dateModified":"2026-07-11T01:18:27.161Z","description":"enable_seqscan = off does not disable sequential scans in PostgreSQL — it only penalizes them so the planner avoids them when alternatives exist. If no usable...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/d9efa64f2231b66e9427570268e55ee1?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/d9efa64f2231b66e9427570268e55ee1?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"Planet PostgreSQL","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Planet PostgreSQL","logo":"https://media.daily.dev/image/upload/logos/placeholder.jpg","url":"https://daily.dev/sources/planet-postgresql"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/all-your-gucs-in-a-row-enable-seqscan-ope0ha3wx","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"postgresql","timeRequired":"PT4M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Planet PostgreSQL","item":"https://daily.dev/sources/planet-postgresql"},{"@type":"ListItem","position":3,"name":"All Your GUCs in a Row: enable_seqscan"}]} ```