ALTER TABLE workshop_settings
  ADD COLUMN email VARCHAR(120) DEFAULT NULL,
  ADD COLUMN city VARCHAR(80) DEFAULT NULL,
  ADD COLUMN state_name VARCHAR(80) DEFAULT NULL,
  ADD COLUMN state_code VARCHAR(2) DEFAULT NULL,
  ADD COLUMN pincode VARCHAR(10) DEFAULT NULL,
  ADD COLUMN pan VARCHAR(10) DEFAULT NULL,
  ADD COLUMN sac_code VARCHAR(8) DEFAULT '998714',
  ADD COLUMN gst_rate DECIMAL(5,2) NOT NULL DEFAULT 18.00,
  ADD COLUMN bank_name VARCHAR(80) DEFAULT NULL,
  ADD COLUMN bank_account VARCHAR(30) DEFAULT NULL,
  ADD COLUMN bank_ifsc VARCHAR(15) DEFAULT NULL,
  ADD COLUMN upi_id VARCHAR(80) DEFAULT NULL;

UPDATE workshop_settings
SET tax_one_name = COALESCE(NULLIF(tax_one_name, ''), 'CGST'),
    tax_two_name = COALESCE(NULLIF(tax_two_name, ''), 'SGST'),
    invoice_header = COALESCE(NULLIF(invoice_header, ''), 'TAX INVOICE'),
    sac_code = COALESCE(NULLIF(sac_code, ''), '998714')
WHERE id = 1;