Read from DB directly

[adis-io]

For example, I want to read key from DB directly, not from cache. Is it possible?

[huacnlee]

Why? What difference?

[adis-io]

I use two rails apps in one machine. They have shared classes, models and etc through rails engine. So when I change values from one app changes not visible in other app. It would be good if I can fetch values from DB something like that: Setting.mykey!

[mrj]

The exclamation mark variant is a good idea.

Another reason to bypass the cache is when you want to lock a setting when reading it (SELECT...FOR UPDATE) to control exclusive access to a resource.

[MichaelSp]

Same here. Value changes in the DB sometimes without the rails app noticing. So I need a way to invalidate the cache or reload directly.

[mlensment]

Second that.

[nykma]

+1 for this.

[prashantham]

+1. Is there any other way to reload setting?

[jpbullalayao]

Would love to load directly from DB as well

[idl3]

We can mark the settings (key/global) as stale and retrieve the new one for caching if we still want the performance gains. Much like a timestamp for last updated?

[brateq]

Same problem here, but on Elastic Beanstalk from Amazon. After update in form, rest of the app (like workers) doesn't know about change and still uses cached variable. How can I force to reload cached settings?

[kabasakalis]

For object scoped settings, I found that this works:

@page = Page.find(params[:id])

@page.settings.unscoped.find_by(var: :setting_id, thing_id: @page.id, thing_type: 'Page')

[erbunao]

I was wondering why was this closed? Was there a resolution/workaround to force reload?

[huacnlee]

https://github.com/ruby-china/homeland/blob/master/app/controllers/admin/site_configs_controller.rb#L24

[erbunao]

https://github.com/ruby-china/homeland/blob/master/app/controllers/admin/site_configs_controller.rb#L24

@huacnlee Apologies for not getting what the line means. Could you elaborate a bit?

[huacnlee]

2.6.3 :002 > Setting.all
 => #<ActiveRecord::Relation [...]>
2.6.3 :002 > Setting.find_by(var: "setting_id")