You've created a table called cassiggnments with two 'g's
Rails seed.rb can't find table that exists in schema and SQL
-
30-05-2022 - |
Вопрос
Class is a reserved word, so I have changed the table name from class_assignment
to cassignments
to avoid any chance that that is the error causing it (despite me having class_instruction(s)
. I have tried plural and singular versions, and still get the error. The cassignments
table is a middle table for the many to many relationship between assignments
and class_instructions
.
Schema :
ActiveRecord::Schema.define(:version => 20130524160107) do
create_table "assignments", :force => true do |t|
t.string "name"
t.string "fractionRepresentations"
....etc...
t.datetime "created_at", :null => false
t.datetime "updated_at", :null => false
end
create_table "cassiggnments", :force => true do |t|
t.integer "class_instruction_id"
t.integer "assignment_id"
t.datetime "created_at", :null => false
t.datetime "updated_at", :null => false
end
add_index "cassiggnments", ["assignment_id"], :name => "index_class_assignment_on_assignment_id"
add_index "cassiggnments", ["class_instruction_id"], :name => "index_class_assignment_on_class_instruction_id"
create_table "class_instructions", :force => true do |t|
t.string "name"
t.datetime "time"
t.datetime "created_at", :null => false
t.datetime "updated_at", :null => false
t.integer "person_id"
end
add_index "class_instructions", ["person_id"], :name => "index_class_instructions_on_person_id"
....etc....
end
Trying to seed the db in the seed.rb
# ClassInstruction Assignment
cia1 = Cassignment.create({ class_instruction_id: 4, assignment_id: 1 }, :without_protection => true ).save!
and I get the error:
rake aborted!
Could not find table 'cassignments'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.2/lib/active_record/connection_adapters/sqlite_adapter.rb:465:in `table_structure'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.2/lib/active_record/connection_adapters/sqlite_adapter.rb:346:in `columns'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.2/lib/active_record/connection_adapters/schema_cache.rb:12:in `block in initialize'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.2/lib/active_record/model_schema.rb:228:in `yield'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.2/lib/active_record/model_schema.rb:228:in `default'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.2/lib/active_record/model_schema.rb:228:in `columns'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.2/lib/active_record/model_schema.rb:243:in `column_defaults'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.2/lib/active_record/base.rb:479:in `initialize'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.2/lib/active_record/persistence.rb:44:in `new'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.2/lib/active_record/persistence.rb:44:in `create'
/Users/special/dev/SoundOfFractions/db/seeds.rb:83:in `<top (required)>'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/activesupport-3.2.2/lib/active_support/dependencies.rb:245:in `load'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/activesupport-3.2.2/lib/active_support/dependencies.rb:245:in `block in load'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/activesupport-3.2.2/lib/active_support/dependencies.rb:236:in `load_dependency'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/activesupport-3.2.2/lib/active_support/dependencies.rb:245:in `load'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/railties-3.2.2/lib/rails/engine.rb:520:in `load_seed'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.2/lib/active_record/railties/databases.rake:309:in `block (2 levels) in <top (required)>'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/task.rb:246:in `call'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/task.rb:246:in `block in execute'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/task.rb:241:in `each'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/task.rb:241:in `execute'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/task.rb:184:in `block in invoke_with_call_chain'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/task.rb:177:in `invoke_with_call_chain'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/task.rb:205:in `block in invoke_prerequisites'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/task.rb:203:in `each'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/task.rb:203:in `invoke_prerequisites'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/task.rb:183:in `block in invoke_with_call_chain'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/task.rb:177:in `invoke_with_call_chain'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/task.rb:170:in `invoke'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.2/lib/active_record/railties/databases.rake:252:in `block (2 levels) in <top (required)>'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/task.rb:246:in `call'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/task.rb:246:in `block in execute'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/task.rb:241:in `each'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/task.rb:241:in `execute'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/task.rb:184:in `block in invoke_with_call_chain'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/task.rb:177:in `invoke_with_call_chain'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/task.rb:170:in `invoke'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/application.rb:143:in `invoke_task'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/application.rb:101:in `block (2 levels) in top_level'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/application.rb:101:in `each'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/application.rb:101:in `block in top_level'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/application.rb:110:in `run_with_threads'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/application.rb:95:in `top_level'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/application.rb:73:in `block in run'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/application.rb:160:in `standard_exception_handling'
/Users/special/.rvm/gems/ruby-1.9.3-p362/gems/rake-10.0.4/lib/rake/application.rb:70:in `run'
/Users/special/.rvm/gems/ruby-1.9.3-p362/bin/ruby_noexec_wrapper:14:in `eval'
/Users/special/.rvm/gems/ruby-1.9.3-p362/bin/ruby_noexec_wrapper:14:in `<main>'
Tasks: TOP => db:setup => db:seed
The only strange thing is that despite my migrations, I didn't get a cassignment.rb
model, so I had to manually create that (maybe I didn't use scaffold, what I am normally used to doing, but I digress). So for posterity, here is the cassignment.rb
class Cassignment < ActiveRecord::Base
belongs_to :class_instruction
belongs_to :assignment
end
naming pluralization matches other many to many relationship tables, and seed structures, but I have no clue where I am going wrong, other than the understanding that the seed file can't find the table, that does exist according to the sqlite browser, and is correctly called cassignments
(plural).
Решение
Другие советы
Is this a has_and_belongs_to_many
relationship or a has_many :through
relationship?
HABTM only:
In the former case you don't need the model and it's important that the table name be both of the joining table names in alphabetical order. assignments_class_instructions
In both cases, the correct approach to creating a join is to add instances of one class to instances of the other rather than creating the joins directly.
class_instruction = ClassInstruction.find(4)
class_instruction.assignments << Assignment.find(1)
Also, there is no problem with class_assignments
and ClassAssignment
as table and model names, so that isn't the issue.