is sorting by an associated column supported? about order_query HOT 10 CLOSED

What do you want to achieve? It's a has_many association, so which one of the many do you want it to sort by? Max? Lexicographic?

from order_query.

Apologies, I probably should have used a has_one in the example. Thus it would be a one-to-one join of two tables, sorting by a field in the second table.

from order_query.

For the has_one case this should be sufficient:

point = Sandwich.joins(:topping).seek([:topping_name, :desc, sql: 'toppings.name'])

class Sandwich < ...
  def topping_name
    topping.name
  end
end

from order_query.

@glebm does calling after on that point work for you? I will come up with a replication bit of code.

from order_query.

The result of that is not a point but a Space. You need to call at to get a Point.

from order_query.

Apologies for the delay. Indeed, once I get a Point, calling after on it is where I get the error. I've created a rails spec gist to replicate the error.

The spec creates models Company and Employee, the latter is a has_one association of the former. The spec is designed to connect to a mysql database (in my case, version 5.7.19) via these environment variables:

• DB_HOST
• DB_USERNAME
• DB_PASSWORD
• DB_NAME
• optional: DB_PORT (defaults to 3306)

The test will create the database specified by DB_NAME, create the table structure, then seed the data with a few records: two Employee records, each with a Contract associated with it. Then it runs a test where it defines a space with the sorting on the association, then finds the point at the first record, then calls after to get one record after.

This is the result of the test I'm encountering:

$ DB_HOST=127.0.0.1 DB_USERNAME=<X> DB_PASSWORD=<Y> DB_NAME=order_query rspec spec/association_spec.rb 

...

  1) OrderQuery search sort on secondary join table can fetch 'next' on a Employee point when sorting by contract.contract_type
     Failure/Error: record = space.at(Employee.first).after(false).limit(1)
     
     NoMethodError:
       undefined method `contract_type' for #<Employee id: 1, name: "John", email: "[email protected]">
       Did you mean?  contract
     # ./spec/association_spec.rb:145:in `block (4 levels) in <top (required)>'

Finished in 2.91 seconds (files took 0.89039 seconds to load)
1 example, 1 failure

Failed examples:

rspec ./spec/association_spec.rb:141 # OrderQuery search sort on secondary join table can fetch 'next' on a Employee point when sorting by contract.contract_type

I feel like I must be doing something wrong. Help is appreciated!

from order_query.

Closing as it's old. In case you still need help, consider StackOverflow.

from order_query.

@glebm were you not able to replicate the problem with the gist I created?

from order_query.

I've had a look at your gist. It works if you simply:

1. Pass the correct arguments to order_query

   -space = Employee.joins(:contract).seek([:contract_type, :desc, "contract.contract_type"])
   +space = Employee.joins(:contract).seek([:contract_type, :desc, sql: "contract.contract_type"])

2. Define the contract_type method on Employee:

   delegate :contract_type, to: :contract

There is an example of using sql: in the Readme: https://github.com/glebm/order_query#advanced-example

from order_query.

Hi @glebm , I apologize for not responding to this sooner. I re-reviewed this today and now understand your approach, and also have been able to reproduce it locally. Thanks again for your help!

from order_query.