ERDs, written like DDL

resin is a small language for entity-relationship diagrams. Nullability, keys, foreign and logical references, indexes and audit tables are syntax: resin checks them as you type and draws every reference from the column that holds it.

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Paste DDL. Get an ERD.

Copy DDL from DataGrip or another database tool. Paste it into resin, focus on connected entities, and trace key references.

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orders.erdDiagram
service accounts "Accounts service" {
  external table users "People who sign in" {
    id  bigint  pk
  }
}

table orders "Customer orders" {
  id          bigint       pk
  user_id     bigint       ~> users  "Customer"  index as idx_user_id
  order_no    varchar(32)  uk as uk_order_no  "Order number"
  buyer_name  varchar?     enc  "Buyer name"
  status      varchar      enum(PENDING, PAID, CANCELED)  index as idx_status
  created_at  datetime
  updated_at  datetime
} audit envers(user_id, status)
The orders example drawn by resin: orders, order items and payments, with an external users tableThe orders example drawn by resin: orders, order items and payments, with an external users table