Question

My sql experience is a bit limited, but my Rails is on point.

I’m writing this raw sql :

select payments.payment_number as payment_payment_number, jobs.job_number from payments;

But getting this error :

ERROR 1054 (42S22): Unknown column 'jobs.job_number' in 'field list'

I don’t quite understand what my App is lacking in order to get this properly working. Can someone explain to me in Rails, what I would need to do in order to associate these two data points?

Answer 1

You simply have not JOINed in the jobs table. In order to make use of two tables, you must include both of them in your FROM clause and supply the appropriate JOIN conditions in an ON clause.

SELECT 
  payments.payment_number as payment_payment_number,
  jobs.job_number
FROM
 /* Substitute the correct column name for those in <> here */
 payments JOIN jobs ON payments.<job_number> = jobs.<job_number>

Substitute the correct column relationship names between payments and jobs. I’ve used job_number as the column name in both tables.