-- Back up the database before applying this migration.
-- Retain legacy registration attributes for existing records, but make them
-- optional for new cooperative records that use the streamlined form.
ALTER TABLE businesses
    ADD COLUMN form_number VARCHAR(80) NULL AFTER certificate_number;

UPDATE businesses
SET form_number = CONCAT('LEGACY-', id)
WHERE form_number IS NULL;

ALTER TABLE businesses
    MODIFY COLUMN form_number VARCHAR(80) NOT NULL,
    ADD UNIQUE KEY uq_businesses_form_number (form_number),
    MODIFY COLUMN business_category VARCHAR(120) NULL,
    MODIFY COLUMN owner_name VARCHAR(190) NULL,
    MODIFY COLUMN nature_of_business VARCHAR(255) NULL,
    MODIFY COLUMN registration_date DATE NULL;