我想使用 chartkick 制作每天用户注册数量的折线图,这只需要一行代码,但是它出现了错误。
`undefined method `group_by_day' for #<Class:0x00000004b4fbf0>`
在我的观点中,我有:
<%= line_chart User.group_by_day(:created_at).count %>
错误日志:
Rendered admin/dashboards/index.html.erb within layouts/application (145.2ms)
Completed 500 Internal Server Error in 1018ms
NoMethodError - undefined method `group_by_day' for #<Class:0x00000004b4fbf0>:
activerecord (3.2.14) lib/active_record/dynamic_matchers.rb:55:in `method_missing'
app/views/admin/dashboards/index.html.erb:38:in `_app_views_admin_dashboards_index_html_erb___3330517857505238097_39214860'
actionpack (3.2.14) lib/action_view/template.rb:145:in `block in render'
activesupport (3.2.14) lib/active_support/notifications.rb:125:in `instrument'
actionpack (3.2.14) lib/action_view/template.rb:143:in `render'
actionpack (3.2.14) lib/action_view/renderer/template_renderer.rb:48:in `block (2 levels) in render_template'
actionpack (3.2.14) lib/action_view/renderer/abstract_renderer.rb:38:in `block in instrument'
activesupport (3.2.14) lib/active_support/notifications.rb:123:in `block in instrument'
activesupport (3.2.14) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
activesupport (3.2.14) lib/active_support/notifications.rb:123:in `instrument'
actionpack (3.2.14) lib/action_view/renderer/abstract_renderer.rb:38:in `instrument'
User.includes(:city).group("city.name").count
。 - Mifeng