ALTER TABLE payroll_employee_profiles
  ADD COLUMN vacation_entitlement_days DECIMAL(5,2) NOT NULL DEFAULT 20 AFTER vacation_pay_rate;

ALTER TABLE payroll_absences
  ADD COLUMN certificate_file_path VARCHAR(255) NULL AFTER certificate_received,
  ADD COLUMN certificate_original_name VARCHAR(190) NULL AFTER certificate_file_path,
  ADD COLUMN certificate_mime VARCHAR(120) NULL AFTER certificate_original_name,
  ADD COLUMN certificate_uploaded_at DATETIME NULL AFTER certificate_mime;