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PORails, one-to-many relationship error in rails console
 

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    <p>I need to set up a one to many relationship between my "Teacher" model and my "Robot" model. Each teacher has many robots but each robot only has one teacher.</p> <p>I thought I had it set up properly but when I try to play around with it in rails console typing this:</p> <pre><code>teacher1.robots = [robot1, robot2] </code></pre> <p>where teacher1 is a valid teacher and robot1 and robot2 are both valid robots, yields this error:</p> <pre><code>SQLite3::SQLException: no such column: robots.teacher_id: SELECT "robots".* FROM "robots" WHERE "robots"."teacher_id" = 14 ActiveRecord::StatementInvalid: SQLite3::SQLException: no such column: robots.teacher_id: SELECT "robots".* FROM "robots" WHERE "robots"."teacher_id" = 14 </code></pre> <p>I am very new to Ruby (and Ruby on Rails) but in all the research I've done, I can't find any mistake in the way I've set up my models or migrations... Here are the two model files and the migration.</p> <p>*_create_robots.rb:</p> <pre><code>class CreateRobots &lt; ActiveRecord::Migration def up create_table 'robots' do |t| t.text 'serial' t.references 'teachers' end end def down ; drop_table 'robots' ; end end </code></pre> <p>robot.rb:</p> <pre><code>class Robot &lt; ActiveRecord::Base belongs_to :teacher end </code></pre> <p>teacher.rb:</p> <pre><code>class Teacher &lt; ActiveRecord::Base has_many :robots before_destroy :confirm_no_inventory protected def confirm_no_inventory unless self.usb_cords == 0 and self.simple_snaps == 0 and self.casters == 0 errors.add(:base, "All checked out items must be returned before #{self.name} can be deleted") return false end end end </code></pre> <p>Thank you in advance to anyone who took the time to look through this, any thoughts at all on what the problem is or how to fix it would be greatly appreciated.</p>
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    1. CODid you actually run the migration? `rake db:migrate`
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    2. COyep, I ran it twice and made sure no changes occurred the second time I ran it
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

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