Best way to represent unions with Drizzle?

[benjick]

Hello

I'm currently building a schema that looks like this, but this is pretty scaled down:

interface BaseTask {
  id: string;
  name: string;
}

interface Word {
  id: string;
  left: string;
  right: string;
  type: "word";
}

interface WordTask extends BaseTask {
  leftTitle: string;
  rightTitle: string;
  words: Word[];
}

interface Question {
  id: string;
  text: string;
}

interface ExitTask extends BaseTask {
  questions: Question[];
  type: "exit";
}

type Task = WordTask | ExitTask;

and I'm wondering, what's the best way of representing this in drizzle?

I currently have the following tables to represent the above:

• tasks
• word_tasks
• word_task_words
• exit_tasks
• exit_task_questions

The tasks table has a type column which represents "exit" or "word". Both word_tasks and exit_tasks have a foreign key against tasks and their respective subtables have foreign keys against their parent. While this works I feel I have to do so much manual "stitching" when wanting to read a complete task;

• first select the task by id, then determine the type and fetch the related rows, or
• join all subtables and pick out the one I need and then transform the data with typescript a bit

I'm sure there are better ways of doing this, can someone make me a suggestion?

[Angelelz]

This sounds a lot like polymorphic association. Drizzle doesn't have first class support for this yet but it's coming pretty soon. Take a look at this issue for some workarounds. I implemented one of these workarounds myself in one of my projects. #1051

[benjick]

That's great, thank you for the link and for teaching me the name of this concept!