fix(sql): fix aliasing of nested composite FK queries

packages/knex/src/query/CriteriaNode.ts

@@ -86,7 +86,13 @@ export class CriteriaNode<T extends object> implements ICriteriaNode<T> {
   }
 
   renameFieldToPK<T>(qb: IQueryBuilder<T>): string {
-    const joinAlias = qb.getAliasForJoinPath(this.getPath());
+    let joinAlias = qb.getAliasForJoinPath(this.getPath());
+
+    if (!joinAlias && this.parent && [ReferenceKind.MANY_TO_ONE, ReferenceKind.ONE_TO_ONE].includes(this.prop!.kind) && this.prop!.owner) {
+      joinAlias = qb.getAliasForJoinPath(this.parent.getPath());
+      return Utils.getPrimaryKeyHash(this.prop!.joinColumns.map(col => `${joinAlias ?? qb.alias}.${col}`));
+    }
+
     const alias = joinAlias ?? qb.alias;
 
     if (this.prop!.kind === ReferenceKind.MANY_TO_MANY) {

tests/issues/GHx13.test.ts

@@ -0,0 +1,110 @@
+import { Entity, ManyToOne, MikroORM, PrimaryKey, Property, Ref } from '@mikro-orm/sqlite';
+
+abstract class Common {
+
+  @PrimaryKey()
+  orgId!: number;
+
+  @PrimaryKey()
+  id!: number;
+
+}
+
+@Entity()
+class Form extends Common {
+
+  @Property({ nullable: false })
+  name!: string;
+
+}
+
+@Entity()
+class FormSubmission extends Common {
+
+  @ManyToOne({
+    entity: () => Form,
+    ref: true,
+    nullable: true,
+  })
+  form?: Ref<Form>;
+
+}
+
+@Entity()
+class FormSubmissionField extends Common {
+
+  @ManyToOne({
+    entity: () => FormSubmission,
+    ref: true,
+  })
+  submission!: Ref<FormSubmission>;
+
+  @Property({ nullable: false })
+  value!: string;
+
+}
+
+let orm: MikroORM;
+
+beforeAll(async () => {
+  orm = await MikroORM.init({
+    dbName: ':memory:',
+    entities: [Form, FormSubmission, FormSubmissionField],
+  });
+  await orm.schema.refreshDatabase();
+});
+
+beforeEach(async () => {
+  await orm.schema.clearDatabase();
+
+  const form1 = orm.em.create(Form, {
+    orgId: 1,
+    id: 10,
+    name: 'Form 1',
+  });
+
+  const submission = orm.em.create(FormSubmission, {
+    orgId: 1,
+    id: 20,
+    form: form1,
+  });
+
+  const submissionField = orm.em.create(FormSubmissionField, {
+    orgId: 1,
+    id: 30,
+    submission,
+    value: 'James',
+  });
+
+  await orm.em.flush();
+  orm.em.clear();
+});
+
+afterAll(async () => {
+  await orm.close(true);
+});
+
+test('Query through nested relationship', async () => {
+  const submissionField = await orm.em.findOneOrFail(
+    FormSubmissionField,
+    { id: 30 },
+    { populate: ['submission.form'] },
+  );
+
+  expect(submissionField.submission.$.form?.$.name).toBe('Form 1');
+  orm.em.clear();
+
+  const submissionFields = await orm.em.find(
+    FormSubmissionField,
+    {
+      submission: {
+        form: {
+          orgId: 1,
+          id: 10,
+        },
+      },
+    },
+  );
+
+  expect(submissionFields).toHaveLength(1);
+});