ALTER TABLE customers ADD COLUMN IF NOT EXISTS contact_name VARCHAR(100) NOT NULL DEFAULT '';
ALTER TABLE customers ADD COLUMN IF NOT EXISTS phone VARCHAR(30) NOT NULL DEFAULT '';
ALTER TABLE customers ADD COLUMN IF NOT EXISTS comments VARCHAR(1000) NOT NULL DEFAULT '';
ALTER TABLE customers ADD COLUMN IF NOT EXISTS morning_start CHAR(5) NULL;
ALTER TABLE customers ADD COLUMN IF NOT EXISTS morning_end CHAR(5) NULL;
ALTER TABLE customers ADD COLUMN IF NOT EXISTS afternoon_start CHAR(5) NULL;
ALTER TABLE customers ADD COLUMN IF NOT EXISTS afternoon_end CHAR(5) NULL;
ALTER TABLE customers ADD COLUMN IF NOT EXISTS late_night_start CHAR(5) NULL;
ALTER TABLE customers ADD COLUMN IF NOT EXISTS late_night_end CHAR(5) NULL;
ALTER TABLE customers ADD COLUMN IF NOT EXISTS updated_at VARCHAR(24) NULL;
ALTER TABLE customer_addresses ADD COLUMN IF NOT EXISTS city VARCHAR(100) NOT NULL DEFAULT '';
ALTER TABLE customer_addresses ADD COLUMN IF NOT EXISTS street VARCHAR(120) NOT NULL DEFAULT '';
ALTER TABLE customer_addresses ADD COLUMN IF NOT EXISTS building_number VARCHAR(20) NOT NULL DEFAULT '';