# arel-mysql-index-hint

Add index hint to MySQL query in Arel.

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## Installation

Add this line to your application's Gemfile:

```ruby
gem 'arel-mysql-index-hint'
```

And then execute:

    $ bundle

Or install it yourself as:

    $ gem install arel-mysql-index-hint

## Usage

```ruby
Article.hint(idx_article: :force)
#=> "SELECT `articles`.* FROM `articles` FORCE INDEX (`idx_article`)"

Article.joins(:comments).hint(articles: {idx_article: :use})
#=> "SELECT `articles`.* FROM `articles` USE INDEX (`idx_article`) INNER JOIN `comments` ON `comments`

Article.joins(:comments).hint(comments: {idx_comment: :force})
#=> "SELECT `articles`.* FROM `articles` INNER JOIN `comments` FORCE INDEX (`idx_comment`) ON `comments"
```

## Related Links

* [MySQL::MySQL 5.6 Reference Manual::13.2.9.3 Index Hint Syntax](https://dev.mysql.com/doc/refman/5.6/en/index-hints.html)