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【单选题】
现有订单表 orders ,包含用户信息 userid 、产品信息 productid ,下列()能返回至少被订购过两次的 productidA.
select productid from orders wherecount(productid)>1
B.
select productid from orders where max(productid)>1
C.
select productid from orders where havingcount(productid)>1 group by productid
D.
select productid from orders group by productid having count(productid)>1
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举一反三
【单选题】Which of the following is valid for a “first-best” world?
A.
Social Marginal Benefit (SMB) > Price (P) = Buyer’s Private Marginal Benefit (MB) = Seller’s Private Marginal Cost (MC) = Social Marginal Cost (SMC)
B.
Social Marginal Cost (SMC) > Price (P) = Buyer’s Private Marginal Benefit (MB) = Seller’s Private Marginal Cost (MC) = Social Marginal Benefit (SMB)
C.
Price (P) = Buyer’s Private Marginal Benefit (MB) = Seller’s Private Marginal Cost (MC) = Social Marginal Cost (SMC) = Social Marginal Benefit (SMB)
D.
Social Marginal Benefit (SMB) > Social Marginal Cost (SMC)
【单选题】Choose the best answer. 选择最佳答案。 Every human being, no matter what he is doing, gives off body heat. The usual problem is how to dispose of it. But the designers of the Johnstown campus of the Universi...
A.
The heat is supplied by human bodies only.
B.
The heat is supplied by both human bodies and other heat-emitting objects.
C.
The heat is supplied by both human bodies and conventional fuel.
D.
The heat is supplied by human bodies, other heat-emitting objects, and conventional fuel.
【简答题】下面属于运筹学研究工作步骤的有
【单选题】Which of the following statements is not true?
A.
Autumn thoughts is a sanqu poem.
B.
Autumn thoughts is one of Ma Zhiyuan’s representative works.
C.
The Injustice to Dou E is a Sanqu poem
D.
The Injustice to Dou E is Guan Hanqing’s best known variey play.
【简答题】The day Shiloh come, we’re having us a big Sunday dinner. Dara Lynn’s dipping bread in her glass of cold tea, the way she likes, and Becky pushes her beans over the edge of her plate in her rush to ge...
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