问题
填空题
数据库模式是数据库中全体数据的逻辑结构和特征的描述，模式的一个具体值称为模式的一个______。
答案
参考答案：实例
解析： 模式是数据库全体数据的逻辑结构和特征的描述，不涉及到具体的值，一个模式可以有很多实例。模式反映的是数据的结构和联系，而实例反映的是数据库某一时刻的状态，模式是相对稳定的，实例是相对变动的。
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数据库模式是数据库中全体数据的逻辑结构和特征的描述，模式的一个具体值称为模式的一个______。
参考答案：实例
解析： 模式是数据库全体数据的逻辑结构和特征的描述，不涉及到具体的值，一个模式可以有很多实例。模式反映的是数据的结构和联系，而实例反映的是数据库某一时刻的状态，模式是相对稳定的，实例是相对变动的。
Is there anything more important than health? I don’t think so. “Health is the greatest wealth.” wise people say. You can’t be good at your studies or work well when you are ill.If you have a headache, toothache, backache, earache or bad pain in the stomach, if you complain of a bad cough, if you run a high temperature and have a bad cold, or if you suffer from high or low blood pressure, I think you should go to the doctor. The doctor will examine your throat, feel your pulse, test your blood pressure, take your temperature, sound your heart and lungs, test your eyes, check your teeth or have your chest X-rayed. After that he will advise some treatment, or some medicine. The only thing you have to do is to follow his advice. Speaking about doctor’s advice, I can’t help telling you a funny story. An old gentleman came to see the doctor. The man was very ill. He told the doctor about his weakness, memory loss and serious problems with his heart and lungs. The doctor examined him and said there was no medicine for his disease. He told his patient to go to a quiet place for a month and have a good rest. He also advised him to eat a lot of meat, drink two glasses of red wine every day and take long walks. In other words, the doctor advised him to follow the rule: “Eat with pleasure, drink with pleasure and enjoy life as it is.” The doctor also said that if the man wanted to be well again, he shouldn’t smoke more than one cigarette a day. A month later the gentleman came into the doctor’s office. He looked cheerful and happy. He thanked the doctor and said that he had never felt a healthier man.“ But you know, doctor,” he said, “it’s not easy to begin smoking at my age.” 小题1:The writer thinks that_____.
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