Returning only id of collection type with relations

Questions and Answers
1
System Information
  • Strapi Version: v3.6.2
  • Operating System: Ubuntu
  • Database:
  • Node Version: v12.19.0
  • NPM Version: 6.14.8
  • Yarn Version: 1.22.5

Hi!
I am trying to only return an id and a title of a collection type, however it does not work it still returns its related collection type. I have tried to only return anther field only title works, then it does not return the related collection type. But if i add id it suddenly returns the related to. Same it i only request id. Is this an intended behavior in some way? It is really confusing me.

Below is my code for only returning id that is returning more than just id, when trying to get both id and title i changed columns to [‘id’, ‘title’].

routes.json

{
      "method": "GET",
      "path": "/article-categories/special",
      "handler": "article-category.getArticleCategories",
      "config": {
        "policies": []
      }
    }

article-category.js:

module.exports = {
  getArticleCategories: async ctx => {
    const result = await strapi.query('article-category').model.fetchAll({
      columns: ['id']
    });
    ctx.send(result);
  }
}