Rails4でDBにjsonのカラムを追加することができない

発生している問題・エラーメッセージ

Rails4 で DB に json のカラムを追加しようと考えています。しかし、 bundle exec rake db:migrate を実行しようとすると、エラーが出てしまい、それ以降進まなくなっています。

もし、わかる方がいらしたら、嬉しいです。

== 20190123214656 AddPlansToImages: migrating =================================
-- add_column(:images, :plans, :json)
rake aborted!
StandardError: An error has occurred, all later migrations canceled:

Mysql2::Error: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'json' at line 1: ALTER TABLE `images` ADD `plans` json
/Users/hiroshi/Desktop/sunny/db/migrate/20190123214656_add_plans_to_images.rb:3:in `change'

Caused by:
ActiveRecord::StatementInvalid: Mysql2::Error: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'json' at line 1: ALTER TABLE `images` ADD `plans` json
/Users/hiroshi/Desktop/sunny/db/migrate/20190123214656_add_plans_to_images.rb:3:in `change'

Caused by:
Mysql2::Error: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'json' at line 1
/Users/hiroshi/Desktop/sunny/db/migrate/20190123214656_add_plans_to_images.rb:3:in `change'
Tasks: TOP => db:migrate
(See full trace by running task with --trace)

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該当のソースコード

コンソール

$ rails generate migration AddPlansToImages plans:json

 rake db:migrate

Gemfile

source 'https://rubygems.org'

# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
gem 'rails', '4.2.8'
# Use mysql as the database for Active Record
gem 'mysql2', '0.3.18'
# Use SCSS for stylesheets
gem 'sass-rails', '~> 4.0.2'
# Use Uglifier as compressor for JavaScript assets
gem 'uglifier', '>= 1.3.0'
# Use CoffeeScript for .coffee assets and views
gem 'coffee-rails', '~> 4.1.0'
# See https://github.com/rails/execjs#readme for more supported runtimes
# gem 'therubyracer', platforms: :ruby

# Use jquery as the JavaScript library
gem 'jquery-rails'
# Turbolinks makes following links in your web application faster. Read more: https://github.com/rails/turbolinks
gem 'turbolinks'
# Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
gem 'jbuilder', '~> 2.0'
# bundle exec rake doc:rails generates the API under doc/api.
gem 'sdoc', '~> 0.4.0', group: :doc

# Use ActiveModel has_secure_password
# gem 'bcrypt', '~> 3.1.7'

# Use Unicorn as the app server
# gem 'unicorn'

# Use Capistrano for deployment
# gem 'capistrano-rails', group: :development

group :development, :test do
  # Call 'byebug' anywhere in the code to stop execution and get a debugger console
  gem 'byebug'
end

group :development do
  # Access an IRB console on exception pages or by using <%= console %> in views
  gem 'web-console', '~> 2.0'

  # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
  gem 'spring'
end

gem 'pry-rails'
gem 'compass-rails','~> 2.0'
gem 'sprockets', '2.11.0'
#pagenation
gem 'kaminari'
#login_logout
gem 'devise'
gem 'paperclip'

#chat
gem 'websocket-rails'
gem 'faye-websocket', '0.10.0'
#image
gem 'carrierwave'
gem 'rmagick'
#date
gem 'momentjs-rails'
gem 'bootstrap3-datetimepicker-rails'

db/migrate

class AddPlansToImages < ActiveRecord::Migration
  def change
    add_column :images, :plans, :json
  end
end

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補足情報 (OS, ツールのバージョンなど)

• MySQL のバージョン
  mysql Ver 14.14 Distrib 5.7.19, for osx10.12 (x86_64) using EditLine wrapper