[9.x] Unnecessary check for columns when paginating with joins

[PauBenetPrat]

This was added on this PR #32691 at this specific commit:
98a242e

A part from that, there is no way to select null columns, always
receiving array(null) instead.

On the other hand, if we join tables and use select *, we could be using
diferent fields from each table but it always breaks when paginating because of
duplicate column name 'id'.

[taylorotwell]

Give me an example query that breaks currently.

[PauBenetPrat]

It's on the test @taylorotwell testBasicJoinsWithPaginateGroupingAndSelectingAsterisk.

With current code it returns:

select * from "users" inner join "contacts" on "users"."id" = "contacts"."id" group by "user_id") as "aggregate_table"

And this returns Duplicate column id error.

Thanks!

[taylorotwell]

Can you provide the real Eloquent query from your application that is breaking?

[PauBenetPrat]

Hi, here is my query:

DB::table('orders')
  ->leftJoin('order_contents','order_contents.order_id', '=', 'orders.id')
  ->groupBy('orders.created_at')->select('*')->paginate(20)

Results into this:

Illuminate\Database\QueryException with message 'SQLSTATE[42S21]: Column already exists: 1060 Duplicate column name 'id' (SQL: select count(*) as aggregate from (select * from `GS_orders` left join `GS_order_contents` on `GS_order_contents`.`order_id` = `GS_orders`.`id` group by `GS_orders`.`created_at`) as `aggregate_table`)'

Would it help if I add my Order and OrderContent model definition?

[taylorotwell]

To me it just looks like your query is broken? Select the columns you want and resolve the ambiguity?

[PauBenetPrat]

Hi @taylorotwell,
It make no sense to me that paginating a query fails and not paginating it not:

$query =  DB::table('orders')
  ->leftJoin('order_contents','order_contents.order_id', '=', 'orders.id')
  ->groupBy('orders.created_at')->select('*');

$query->paginate(20);  // FAILS

$query->get();       // SUCCESS

Thats just an example of a query that fails. We've got this kind of queries on a 100 reports (more or less) and them are selecting *. After the select we use the fields that we need and when there is an ambiguity error we specify which table should be used.

For example we've got ContentReport and OrderReport which extends one from the other. Now a days we are using a select * on OrderReport.

To select the appropriate tables now we should select orders.* on OrderReport and order_contents.* (overriding parent method) on ContentReport. That may seem simple, but we can not assure all results will stay the same on production 😞