BelongSQL

Answer "belongs to" questions about your relational database.

About

Note, this project is in active development, with an unstable API and limited DB support (only postgres).

While this project is obviated by ORMs, most ORMs I found were:

• heavy weight - tons of dependencies, large API to learn
• did not provide auto-schema-reading - i.e. I have to write a ton of views / configurations to do a simple task

I am using this as a stop-gap until my project grows to need an ORM, or I find a lightweight ORM satisfying current needs.

Motivation

A common design pattern in relational databases is to create a hierarchy (directed graph) of objects. In many applications, it is common to ask if a child object in this hierarchy belongs to parent object. BelongSQL makes answering these types of questions simple.

Example

A freelancer billing app's database may represent a belonging to an belonging to a belonging to a . Take the case that permissions to edit a are assigned at the level (so that a may modify only their own s). If we are implementing an API endpoint for editing invoices, say /edit/lineitem/:id, with cookie or body data identifying a contractor_id, we would need to validate that the at :id belongs to the at contractor_id. To do so in raw SQL, we might write a query like:

SELECT
  COUNT(1)
FROM contractor
JOIN task
  ON task.contractor_id = contractor.id
JOIN invoice
  ON invoice.task_id = task.id
JOIN lineitem
  ON lineitem.invoice_id = invoice.id
WHERE
  contractor.id = 'x'
  AND lineitem.id = 'y'

Compare to BelongSQL:

const graph = SchemaGraph.fromDB(connection);
graph.belongsTo('lineItem', 'x', 'contractor', 'y');

Notably, SchemaGraph requires 0 configuration.