Rails - Understanding how to Query An Objectin Rails 3

if I have the following:

@projects = Permission.where(["user_id >= ?", 21])

Results In:

[#<Permission id: 59, project_id: 13, user_id: 21>, #<Permission id: 59, project_id: 13, user_id: 21>]

I then what to use those project_id 's to QUERY as follows:

AuditLog.where({ :project_id => @projects开发者_如何学JAVA }).limit(10)

But this errors?

NoMethodError: undefined method `project_id' for [#<Permission id: 59, project_id: 13, user_id: 21>]:ActiveRecord::Relation

Ideas? thank you

To start, let's clean up your first query:

@permissions = Permission.where(['user_id >= ?', 21])

This is less misleading about what @permissions is actually storing. Next, remember that it's an array, and what you're saying in the next query is "where project_id is a list of ruby permission objects", and that doesn't make a valid query.

You can get the info you want, though. First, use ruby's array.map method to walk through all permissions and gather their project_id's:

@project_ids = @permissions.map(&:project_id)

Now you can tell the database to grab all audit logs where the project_id is in the list:

@audit_logs = AuditLog.where(['project_id in (?)', @project_ids])

That should give you what you need. Let me know if you have any questions.