Access入门教程 3.4 选择数据库中表和表中的字段
现在屏幕上又出现了信息提示对话框,上面有 数据库 需要存储的客户信息、订单信息等很多内容。 入门 教程 3.4 选择 数据库 中表 和表中的 字段 " /> 看过这些提示信息后,单击“下一步”按钮进入向导的下一步工作。对话框中提了一个问题“请确定是否添加可选
现在屏幕上又出现了信息提示对话框,上面有数据库需要存储的客户信息、订单信息等很多内容。
看过这些提示信息后,单击“下一步”按钮进入向导的下一步工作。对话框中提了一个问题“请确定是否添加可选字段?”。这个对话框分类列出了数据库中可能包含的信息,左边框中是信息的类别,右边框中列的是当前选中的类别中的信息项。
这些信息项的前面都有一个小方框,有的小方框中有一个“√”,表示此信息项被选中了,被选中的信息项将会出现在数据库中,而没有选中的信息项就不会出现在数据库中。我们可以通过单击信息项前的小方框来决定数据库中是否要包含某些信息项,如果信息项前面的小方框是空的,单击它就会出现对勾;如果小方框中有对勾,单击它就会变空。不过要注意,绝大多数的信息项前面的对勾是不能取消的,单击它的时候会出现提示,“此选项不能被取消”。这是因为使用数据库向导建立数据库的时候,向导认为有些信息项是此种类型的数据库必须包含的,它们和数据库中的窗体和报表紧密相关,所以Access不允许我们随便取消这些必选项目。从外观上很容易区分必选项目和非必选项目。用斜体字书写的项目就不是必选项目,可以选择也可以取消;而用正常字体书写的项目都是必选项目,不可以取消的。如果不想再增加什么非必选项目了。就可以进行“下一步”了。

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