alter table错在哪里？

[mylajilaji]

ALTER TABLE stock ADD CONSTRAINT mm UNIQUE (mydate,accounttype,assettype,code,name)
INSERT INTO stock ( mydate, accounttype, assettype, code, name, [number], price, 备注 )
SELECT date()+2, accounttype, assettype, code, name, number, price, 备注
FROM stock
WHERE mydate= (select max(mydate) from stock);

上面的语句运行时出现错误：

ALTER 语句中的语法错误

INSERT INTO stock ( mydate, accounttype, assettype, code, name, [number], price, 备注 )
SELECT date()+2, accounttype, assettype, code, name, number, price, 备注
FROM stock
WHERE mydate= (select max(mydate) from stock);
可以单独运行；没有问题

如何增加
ALTER TABLE stock ADD CONSTRAINT mm UNIQUE (mydate,accounttype,assettype,code,name)
这句话？

[wwwwb]

分两次执行：
1、ALTER TABLE stock ADD CONSTRAINT mm UNIQUE (mydate,accounttype,assettype,code,name)
2、INSERT INTO stock ( mydate, accounttype, assettype, code, name, [number], price, 备注 )
SELECT date()+2, accounttype, assettype, code, name, number, price, 备注
FROM stock
WHERE mydate= (select max(mydate) from stock);

JET SQL一次不能执行多条SQL语句

[wwwwb]

参考：
jet sql是否支持程序流分支？是否能像存储过程那样使用变量？能否多行一起执行？
http://www.access911.net/fixhtm/72FAB51E17DCE9F3.htm?tt=jet%20sql%CA%C7%B7%F1%D6%A7%B3%D6%B3%CC%D0%F2%C1%F7%B7%D6%D6%A7%A3%BF%CA%C7%B7%F1%C4%DC%CF%F1%B4%E6%B4%A2%B9%FD%B3%CC%C4%C7%D1%F9%CA%B9%D3%C3%B1%E4%C1%BF%A3%BF%C4%DC%B7%F1%B6%E0%D0%D0%D2%BB%C6%F0%D6%B4%D0%D0%A3%BF%A1%B6%B2%E9%D1%AF%A1%B7