-- 删除ID为30的客户记录
DELETE FROM customers WHERE T_id = 30;

-- 删除所有电话号码以12开头的客户记录
DELETE FROM customers WHERE T_phone LIKE '12%';
-- 删除ID为001的菜单项记录
DELETE FROM menu_items WHERE M_id = '001';

-- 删除所有价格大于50的菜单项记录
DELETE FROM menu_items WHERE M_price > 50;
-- 删除ID为001的折扣规则记录
DELETE FROM discount_rules WHERE M_id = '001';

-- 删除所有折扣小于0.8的折扣规则记录
DELETE FROM discount_rules WHERE discount < 0.8;
-- 删除ID为TABLE06的餐桌记录
DELETE FROM tables WHERE Cz_id = 'TABLE06';

-- 删除所有状态为空闲的餐桌记录
DELETE FROM tables WHERE Cz_zt = '空闲';
-- 删除ID为01的员工记录
DELETE FROM workers WHERE W_id = '01';

-- 删除所有状态为0的员工记录
DELETE FROM workers WHERE W_stat = 0;
-- 删除ID为27的订单记录
DELETE FROM orders WHERE O_id = 27;

-- 删除所有时间在2024-12-27之前的订单记录
DELETE FROM orders WHERE time < '2024-12-27 00:00:00';
-- 删除ID为20的账单记录
DELETE FROM bills WHERE B_id = 20;

-- 删除所有金额大于50的账单记录
DELETE FROM bills WHERE S_price > 50;