select cusnum,workname from customer,worker where cusnum=(select cusnum from inhotel where customer.cusname=inhotel.cusname) -> workname=(select workname from worker.worknum=inhotel.worknum); ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'workname=(select workname from worker.worknum=inhotel.worknum)' at line 2 mysql>

在这个 SQL 语句中，您需要使用 JOIN 子句来联接多个表，而不是使用嵌套的子查询。您可以尝试以下 SQL 语句：

SELECT customer.cusnum, worker.workname 
FROM customer 
JOIN inhotel ON customer.cusnum = inhotel.cusnum 
JOIN worker ON worker.worknum = inhotel.worknum;

这个语句将会从 `customer`、`inhotel` 和 `worker` 表中检索数据，并使用 `JOIN` 子句将它们连接起来。