Description
https://loopback.io/doc/en/lb4/todo-list-tutorial-sqldb.html#specify-the-foreign-key-constraints-in-todo-model
In your example below.
@model({
settings: {
foreignKeys: {
fk_todo_todoListId: {
name: 'fk_todo_todoListId',
entity: 'TodoList',
entityKey: 'id',
foreignKey: 'todoListId',
},
},
},
})
export class Todo extends Entity {
//etc.
}
When following the setup above to run database migration for my local postgresdb as part of todo example tutorial, I encountered the following error:
Cannot migrate database schema error: column "todoListId" referenced in foreign key constraint does not exist
at Parser.parseErrorMessage (/Users/andywongcheeming/Projects/poc/todo-list/node_modules/pg-protocol/dist/parser.js:283:98)
I was left puzzled why the instructions did not work as expected. I dig up online and my personal ChatGPT to understand if Postgres DB has case-sensitive when comes to table and field naming conventions. It turns out that it does.
When I go back and check my local postgres todo definitions via psql cli.
todo_db=# \d todo
Table "public.todo"
Column | Type | Collation | Nullable | Default
------------+---------+-----------+----------+---------
id | integer | | not null |
title | text | | not null |
desc | text | | |
iscomplete | boolean | | |
todolistid | integer | | |
It turns our the foreign key todolistid comes out as lower case by default when running Loopback db migration tool. The sample @model code above supplied as {foreignKey: 'todoListId'}.
I corrected it to use lower-case, dropped the database and started the migration all over again. The migration works this time.
Thus, I must ask - shouldn't the instructions be updated to use lowercase since the plugin creates tables and field names in lowercase by default?