这个能用吗 CROSS JOIN ?

SELECT name, salary / s.max_money
FROM table_a CROSS JOIN
     (SELECT max(money) as max_money from table_sal) s

你也可以这样做如下，请让我知道它是否适合你。

Select t1.name
      , t1.salary/T2.max_money
 from
   (SELECT name
         , salary, 1 as dummy
           from  table_a ) t1 
  Join
      (SELECT max(money) as max_money
            , 1 as dummy 
              from table_sal) t2
  on t1.dummy = t2.dummy ;