Order/Sort parent based on Childrens

[Aniket-IN]

In my application,
I have MessageThread and Message model.

This is the migration for message_threads table:

            $table->string('sender_number', 15);
            $table->string('receiver_number', 15);

            $table->string('sender_number_receiver_number', 30)->virtualAs('CONCAT(`sender_number`, "-", `receiver_number`)');
            $table->string('receiver_number', 30)->virtualAs('CONCAT(`receiver_number`, "-", `sender_number`)');

            $table->string('contact_name', 75)->nullable();
            $table->unique(['sender_number', 'receiver_number']);

And messages

            $table->string('from', 15);
            $table->string('to', 15);

            $table->string('from_to', 30)->virtualAs('CONCAT(`from`, "-", `to`)');
            $table->string('to_from', 30)->virtualAs('CONCAT(`to`, "-", `from`)');

            $table->text('text')->nullable();

With that, I have relations like this in MessageThread:

    public function messages(): HasManyMerged
    {
        return $this->hasManyMerged(Message::class, ['from_to', 'to_from'], 'sender_number_receiver_number');
    }

It works fine, I mean I can get all messages (incoming, outgoing) from a message thread.

But I want to get a list of Threads, based on Messages.
Like, Thread which has most recent message should be on top, and least recent thread to the bottom.

I'm sure it's not the best solution for messaging, seems too hacky, but this is what I could come up with.
Please suggest some way to sort the threads, or maybe suggest something different all together.

Thanks.

[korridor]

Thanks for the issue. To be honest, currently I can only come up with trickier solutions with subqueries.
But it might be possible to get a very clean solution with the HasOne feature request in the following issue: !11

I hope I find the time to look into that in the following weeks, but I'm not so sure. If you are motivated, you can also provide a PR for the HasOne relation suggestion.

[korridor]

@Aniket-IN Please check out if !13 resolves your problem. It is currently not perfect and I'll add more tests, but I think it is stable enough to test the use case.