-- BIZ8-11: align purchase requests with the existing lightweight project-link pattern.
ALTER TABLE "purchase_requests" ADD COLUMN "project_id" UUID;

CREATE INDEX "idx_purchase_requests_project" ON "purchase_requests"("project_id");

ALTER TABLE "purchase_requests"
  ADD CONSTRAINT "purchase_requests_project_id_fkey"
  FOREIGN KEY ("project_id") REFERENCES "projects"("id")
  ON DELETE SET NULL ON UPDATE CASCADE;