CREATE TABLE "transaction" (
  "id" serial NOT NULL,
  PRIMARY KEY ("id"),
  "expense_id" integer NOT NULL,
  "user_id" integer NOT NULL,
  "amount" integer NOT NULL,
  "currency" character varying(255) NOT NULL,
  "is_income" boolean NOT NULL DEFAULT FALSE,
  "created_at" date NOT NULL,
  "updated_at" date NOT NULL
);

ALTER TABLE "transaction"
ADD FOREIGN KEY ("user_id") REFERENCES "user" ("id") ON DELETE CASCADE ON UPDATE CASCADE;