创建列：
ALTER TABLE yourtable ADD COLUMN combined VARCHAr(50);
更新当前值：
UPDATE yourtable SET combined = CONCAt(zippre, ' - ', city, ', ', state);
自动更新所有未来值：
CREATE TRIGGER insert_triggerBEFORE INSERT ON yourtableFOR EACH ROWSET new.combined = CONCAt(new.zippre, ' - ', new.city, ', ', new.state);CREATE TRIGGER update_triggerBEFORE UPDATE ON yourtableFOR EACH ROWSET new.combined = CONCAt(new.zippre, ' - ', new.city, ', ', new.state);
