My outputs are printed several times if I use Join in query

I have 3 categories and 2 posts in my database, if I do query with Join in Ecto, it shows me 6 outputs, but I need 2 outputs, please see my code :

post = from p in Post,
            join: c in PostCategory,
					 select: %{
						 title: p.title,
						 status: p.status,
						 post_type: p.post_type,
						 category_title: c.title,
						 category_status: c.status,
						 category_language: c.language,

it should be noted that Post referenced to PostCategory like this :

        belongs_to :cms_post_category, TrangellCmsService.Cms.Db.PostCategory, foreign_key: :cms_post_category_id, type: :binary_id

Ohh, I forgot to write where: p.cms_post_category_id ==, , after writing it fixed.