[Spike] Automigrate: no need to specify the order of tables to be migrated

[dhmlau]

Description / Steps to reproduce / Feature proposal

A follow-up story suggested by @bajtos from https://github.com/strongloop/loopback-next/pull/2448#discussion_r280759662

Capturing a summary here When calling the migrate script (npm run migrate) to create tables in PostgreSQL with foreign key constraints, we need to specify the order explicitly, i.e.

await app.migrateSchema({
  existingSchema,
  // The order of table creation is important.
  // A referenced table must exist before creating a
  // foreign key constraint.
  // For PostgreSQL connector, it does not create tables in the
  // right order.  Therefore, this change is needed.
  models: ['TodoList', 'Todo', 'TodoListImage'],

@bajtos suggested opening a new GH issue to find out how to improve our migration tool to not require that explicit order. Ideally, we can migrate tables first and define FK constraints second, then the order would not matter.

Acceptance Criteria

• [ ] Investigate if we only need to specify the order only for PostgreSQL connector
• [ ] Investigate how we can improve the migration tool such that we migrate tables first and define FK constraints second

cc @bajtos @elv1s

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This issue has been marked stale because it has not seen activity within six months. If you believe this to be in error, please contact one of the code owners, listed in the CODEOWNERS file at the top-level of this repository. This issue will be closed within 30 days of being stale.

[stale[bot]]

This issue has been closed due to continued inactivity. Thank you for your understanding. If you believe this to be in error, please contact one of the code owners, listed in the CODEOWNERS file at the top-level of this repository.