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Gary Insley
14,133 PointsACTIVE RECORD - (Mysql2::Error: Table 'biller_development.employees_projects' doesn't exist) - Please help!!!!! :)
I am taking the course Active Record and following along with Hampton. We have got to the HAS_AND_BELONGS_T0_MANY stage. However im having a problem trying to access: Project.first.employee:
This is the code that i entered into IRB and the error message i received: (p = Project.first)
irb(main):003:0> p.employees
Mysql2::Error: Table 'biller_development.employees_projects' doesn't exist: SHOW FULL FIELDS FROM `employees_projects`
ActiveRecord::StatementInvalid: Mysql2::Error: Table 'biller_development.employees_projects' doesn't exist: SHOW FULL FIELDS FROM `employees_projects`
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/connection_adapters/abstract_mysql_adapter.rb:303:in `query'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/connection_adapters/abstract_mysql_adapter.rb:303:in `block in execute'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/connection_adapters/abstract_adapter.rb:373:in `block in log'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activesupport-4.1.4/lib/active_support/notifications/instrumenter.rb:20:in `instrument'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/connection_adapters/abstract_adapter.rb:367:in `log'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/connection_adapters/abstract_mysql_adapter.rb:303:in `execute'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/connection_adapters/mysql2_adapter.rb:228:in `execute'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/connection_adapters/abstract_mysql_adapter.rb:310:in `execute_and_free'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/connection_adapters/abstract_mysql_adapter.rb:451:in `columns'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/connection_adapters/schema_cache.rb:93:in `block in prepare_default_proc'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/connection_adapters/schema_cache.rb:44:in `yield'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/connection_adapters/schema_cache.rb:44:in `columns'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/connection_adapters/schema_cache.rb:97:in `block in prepare_default_proc'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/connection_adapters/schema_cache.rb:50:in `yield'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/connection_adapters/schema_cache.rb:50:in `columns_hash'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/associations/association_scope.rb:47:in `column_for'
... 7 levels...
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/associations/association.rb:97:in `association_scope'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/associations/association.rb:86:in `scope'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/associations/collection_association.rb:404:in `scope'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/associations/collection_proxy.rb:36:in `initialize'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/relation/delegation.rb:106:in `new'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/relation/delegation.rb:106:in `create'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/associations/collection_association.rb:36:in `reader'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activerecord-4.1.4/lib/active_record/associations/builder/association.rb:110:in `employees'
from (irb):3
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/railties-4.1.4/lib/rails/commands/console.rb:90:in `start'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/railties-4.1.4/lib/rails/commands/console.rb:9:in `start'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/railties-4.1.4/lib/rails/commands/commands_tasks.rb:69:in `console'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/railties-4.1.4/lib/rails/commands/commands_tasks.rb:40:in `run_command!'
from /Users/Gary/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/railties-4.1.4/lib/rails/commands.rb:17:in `<top (required)>'
from bin/rails:4:in `require'
from bin/rails:4:in `<main>'
My EmployeesProjects Migration is set up as:
class EmployeesProjects < ActiveRecord::Migration
def change
create_table :employees_projects do |t|
t.belongs_to :employee, :project
t.timestamps
end
end
end
My Projects Module is set up as:
class Project < ActiveRecord::Base
belongs_to :customer
has_and_belongs_to_many :employees, :join_table => "employees_projects"
end
I believe i have followed along word for word and cannot seem to find where i have gone wrong, anyones help would be greatly appreciated.... I have been stuck on this for days and cannot progress.
Thanks
4 Answers
Aimee Ault
29,193 PointsNot sure if you've already tried this, but if you ran your migration (using rake db:migrate from the command line) after you had already loaded Projects.first into your p variable, you may need to reload irb and reassign the variable to reflect any changes you've made.
Gary Insley
14,133 PointsI have added my files to the following GitHub Repository:
Your help would be greatly appreciated, thanks :)
Aimee Ault
29,193 PointsThanks for sharing your code, Gary!
So what's happening there is that you have a has_and_belongs_to_many relationship with Employee on your Project model. Since it can belong to many employees, not just limited to one, you need to access it through employees like:
Project.first.employees
which will return you a collection of all employees it belongs to :)
Gary Insley
14,133 PointsHi Aimee this is what i was doing, However i was first storing Project.first in a variable called p and then accessing employees on p:
p = Project.first
p.employees
However it was returning Mysql2::Error: Table 'biller_development.employees_projects' doesn't exist
If there is nothing wrong with my code is there anything else that could case this error??
Gary Insley
14,133 PointsGary Insley
14,133 PointsHi Aimee,
Thanks for responding, ive been stuck on this for ages now. I've tried db:migrate again and now it is returning an error of:
NoMethodError: undefined method 'employee' for #<Project:.........
Any ideas?? Thanks