Support recursive relationships

[ridsameer]

Problem

Let's say I have a table called categories. This table can refer to itself as a foreign key with parentCategory.
So a categories can have many subcategories, and subcategories can also have subcategories, with an unlimited combination. The idea is to support recursive queries to easily query them along with their sub categories.

Suggested solution

Some valid implementation of something similar to Postgres WITH RECURSIVE
https://www.postgresqltutorial.com/postgresql-recursive-query/

Alternatives

N/A

Additional context

N/A

[sbrichardson]

For data structures like this, The best way I've found to handle with GraphQl in general (unrelated to prisma) is to flatten the tree to one level, and track the parentId/index etc as properties. Then have a simple/fast recursive function that builds the tree or converts back to a flat list etc.

This is more of a Graphql limitation (not supporting recursion) but I've found working with a flattened list vs (n)tree has other benefits, like being able to mutate the tree as a linked list/doubly linked list etc).

[pantharshit00]

Self referencing relations are possible in the Prisma schema today. See docs on them here: https://www.prisma.io/docs/reference/tools-and-interfaces/prisma-schema/relations#self-relations

That can get you started. But in general thanks for opening this issue for WITH RECURSIVE CTEs. This can improve experience here.

For now you can also use a raw query here: https://www.prisma.io/docs/reference/tools-and-interfaces/prisma-client/raw-database-access

[ridsameer]

Thanks @pantharshit00 . Thankfully this isn't required in my project right now but is in a roadmap for another personal project so thought I'd bring it up.

Thanks again

[masihjahangiri]

I have used raw queries for recursive queries.
I Think It's simple to implement in Prisma and it's very common in every project.

[danielolaviobr]

Couldn't a possible solution be having a decorator in our model saying that a certain relation is included by default when we query that table? So that when we would query for the tree structure, we would only query for the rows that have the parentId as null and the children would come by default, even in the children's children.

[lumenwrites]

Hey guys, I'm struggling with the same issue, and would really like to see this feature. Someone on StackOverflow suggested that I leave a comment here to help the developers track the demand for this feature.

Meanwhile, can someone please help me to figure out how to write a raw query that accomplishes the same thing? I'm not too great at SQL, and I'm relatively new to Prisma, and I'd really love to find a solution to this.

[brielov]

I've been waiting for this feature too. It would be awesome to see this feature gain some traction.