基本操作题答案：
4、update products set 销售价格=进货价格*(1+18.98/100)
简单应用题答案：
1、第一处将“=”改为“in”, 第二处将“*”改为“学号”, 第三处将“学号”改为“课程号”
综合应用题答案：
“计算”菜单项的过程代码为：
SELECT 股票代码,COUNT(*) AS 买入次数,MAX(单价) AS 最高价 FROM STOCK_MM WHERE 买卖标记 GROUP BY 股票代码 ;
ORDER BY 股票代码 INTO ARRAY aaa
DELETE FROM STOCK_CS
INSERT INTO STOCK_CS FROM ARRAY aaa
SELECT * TOP 1 FROM STOCK_CS ORDER BY 买入次数 DESC INTO TABLE STOCK_X
“退出”菜单项的命令代码为：set sysmenu to default