# Posts tagged Databases

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## [Common Table Expressions in Ruby on Rails](https://by-robots.dev/posts/common-table-expressions-in-ruby-on-rails.md)

Published on 19 March 2023. Tagged Databases, Ruby on Rails, and SQL.

A practical look at Common Table Expressions in Ruby on Rails. Covers writing CTEs as raw SQL in Rails 7.0 and below, the N+1 query problem that raw SQL results introduce (because ActiveRecord's preload cannot be used), a workaround that calls the preloader directly, and the cleaner approach added in Rails 7.1 — the ActiveRecord-native "with" method, which generates the CTE and restores full preload support.