-- Your SQL goes here

ALTER TABLE authentication
    ALTER COLUMN authentication_connector DROP NOT NULL,
    ALTER COLUMN merchant_connector_id DROP NOT NULL,
    ADD COLUMN IF NOT EXISTS authentication_client_secret VARCHAR(128) NULL,
    ADD COLUMN IF NOT EXISTS force_3ds_challenge BOOLEAN NULL,
    ADD COLUMN IF NOT EXISTS psd2_sca_exemption_type "ScaExemptionType" NULL,
    ADD COLUMN IF NOT EXISTS return_url VARCHAR(2048) NULL,
    ADD COLUMN IF NOT EXISTS amount BIGINT,
    ADD COLUMN IF NOT EXISTS currency "Currency";