Help me please with syntax error at or near "DESC"

[nvoynov]

Hi,

I'm trying to order a dataset by sort of incoming param order that is a hash with fields and directions, like {:title => :asc, :price => :desc}. Not so obvious code unfortunately

def q(..., order: {}, ...)
    # skipped...
    orderfu = proc{|dataset|
      if order.any?
        aorder = order.map{|k, v| v == :asc ? k : Sequel.desc(k) }
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        dataset.order(aorder)
      else
        dataset
      end
    }
    ds = @db[:articles]
    ds.then{|ds| filterfu.(ds)}
      .then{|ds| orderfu.(ds)}
      .then{|ds| offset > 0 ? ds.offset(offset) : ds}
      .then{|ds| limit > 0 ? ds.limit(limit) : ds }
      .all
end

Things are good when I pass order parameters with :asc, but when any field direction is :desc, I got the following error:

# store.q(Article, order: {:price => :asc, :id => :desc}, limit: 3)

Sequel::DatabaseError: PG::SyntaxError: ERROR:  syntax error at or near "DESC"
LINE 1: SELECT * FROM "articles" ORDER BY ("price", "id" DESC) LIMIT...

Gemfile.lock

pg (1.4.5-x64-mingw32)
sequel (5.64.0)

Connection

@db = Sequel.connect(conns)
@db.extension :pg_array, :pg_json
Sequel.extension :pg_array_ops, :pg_json_ops

PG14

$ docker run --name orders-pg -p 5432:5432 -e POSTGRES_USER=postgres -e POSTGRES_PASSWORD=postgres -e POSTGRES_DB=store -d docker.io/postgres:14

Database schema, PG14

DROP TABLE IF EXISTS articles;
DROP TABLE IF EXISTS orders;

-- origin Entities::Article
CREATE TABLE articles (
  id uuid PRIMARY KEY,
  title text,
  price money
);

-- origin Entities::Order
CREATE TABLE orders (
  id uuid PRIMARY KEY,
  created_at timestamp with time zone,
  total money,
  articles jsonb array
);

I'm just doing my first steps with PG and Sequel trying to create a sort of mapper from PORO into PG. And I even succeeded with the whole thing except ordering. Just weird...

[adam12]

What happens if you pass separate arguments to Sequel::Dataset#order instead of an Array.

dataset.order(*aorder)

[nvoynov]

Thanks!