ぐるぐるSQLは止めてくださいという話 - Qiita
Deleted articles cannot be recovered. Draft of this article would be also deleted. Are you sure you want to delete this article? 1. はじめに 仕事の都合で DB/SQL の性能問題を調査する機会が少なくありませんが（決してメインの仕事ではないですが）、その中でよく出くわす問題の１つに「ぐるぐるSQL」（もしくは「ぐるぐる系」）といわれる、ループで大量の SQL 文を呼び出しているものがあります。 感覚ですが、私の周りでは OLTP 系システムの DB/SQL の性能問題の原因の割合は以下のように感じています。 30%：ぐるぐる SQL 20%：SQL 文の書き方が不適切 15%：索引がない or 不適切 15%：パーズが遅い 10%：データモデルがおかしい 1
Two ways for testing preloading/eager-loading of ActiveRecord associations in Rails
Two ways for testing preloading/eager-loading of ActiveRecord associations in Rails … and check why 5600+ Rails engineers read also this Two ways for testing preloading/eager-loading of ActiveRecord associations in Rails As a developer who cares about performance you know to avoid N+1 queries by using #includes, #preload or #eager_load methods . But is there a way of checking out that you are doin
GraphQL and Performance in Rails
We looked previously at getting set up with GraphQL on Rails. We defined some queries, some mutations, and had a good time doing so! But what if I told you that with only a few hundred records in the database, it's possible to write a query that brings our server grinding to a halt? In this article, we'll look at three ways to avoid performance issues with GraphQL in your Rails app, and then at a
Batching – A powerful way to solve N+1 queries every Rubyist should know
In this post, I’m going to tell you about batching as a technique to help avoid N+1 queries, existing battle-tested tools like Haskell Haxl and JavaScript DataLoader, and how similar approaches can be used in any Ruby program. Here is a translated Japanese version of the blog post. What are N+1 queries?First, let’s find out what N+1 queries are and why they are called that. Imagine, we have 2 SQL
N+1 Queries or Memory Problems: Why not Solve Both?
This post is going to help save you money if you're running a Rails server. It starts like this: you write an app. Let's say you're building the next hyper-targeted blogging platform for medium length posts. When you login, you see a paginated list of all of the articles you've written. You have a Post model and maybe for to do tags, you have a Tag model, and for comments, you have a Comment model
Tips for Writing Fast Rails: Part 1 - FastRuby.io | Rails Upgrade Service
Published on October 11, 2016. Updated on March 5, 2020. Rails opens a new window is a powerful framework. You can write a lot of features in a short period of time. In the process you can easily write code that performs poorly. At OmbuLabs opens a new window we like to maintain Ruby on Rails applications opens a new window . In the process of maintaining them, adding features and fixing bugs, we
How to Diagnose Ruby on Rails N + 1 Query Problems
Diagnosing performance problems in a production Ruby on Rails application can be deceptively complex. When constructing a new application or expanding the features of an existing one, development environments that are not subject to typical production web traffic may not make performance issues evident. In those instances, the use of some simple (and mostly free) tools can help diagnose performanc
RailsでN+1 countクエリを潰すactiverecord-precountを作った - k0kubun's blog
追記: 2017/09/06 少しAPIが冗長なもののActiveRecordへのモンキーパッチが少ないバージョン activerecord-precounter というのを作りました。こちらの方がバグりにくいはずなので、現在はactiverecord-precounterの方を使うことが推奨されます。 github.com 概要 N+1 countクエリを最大11.7倍速くできるactiverecord-precountというgemを作った。 *1 k0kubun/activerecord-precount N+1 countクエリ Tweet.all.each do |tweet| p tweet.favorites.count end # SELECT `tweets`.* FROM `tweets` # SELECT COUNT(*) FROM `favorites` WHERE
1
リリース、障害情報などのサービスのお知らせ
最新の人気エントリーの配信
j次のブックマーク
k前のブックマーク
lあとで読む
eコメント一覧を開く
oページを開く
https://jasacuantop.com/
GitHub - exAspArk/batch-loader: :zap: Powerful tool for avoiding N+1 DB or HTTP queries
GitHub - k0kubun/activerecord-precount: N+1 count query killer for ActiveRecord