Access入门教程 9.6 查询的数据表视图
我们已经把需要的字段都添加到 查询 中了,现在来看看建立的“ 查询 ”的结果。 上一课中讲过“表”可以在设计 视图 和 数据表 视图 中切换,“ 查询 ”同样也可以在设计 视图 和 数据表 视图 中切换。将表切换到 数据表 视图 ,就可以看到“ 查询 ”结果了
我们已经把需要的字段都添加到查询中了,现在来看看建立的“查询”的结果。
上一课中讲过“表”可以在设计视图和数据表视图中切换,“查询”同样也可以在设计视图和数据表视图中切换。将表切换到数据表视图,就可以看到“查询”结果了。在Access中,在几个视图之间切换是非常简单的。只要将鼠标移动到工具栏左上角的第一个工具按钮处,就会弹出一个“视图”提示标签,单击它就可以从查询设计视图切换到数据表视图。 查询的数据表视图看起来很像上一课讲的表,但它们之间还是有很多差别的。
在查询数据表中无法加入或删除列,而且不能修改查询字段的字段名。这是因为由查询所生成的数据值并不是真正存在的值,而是动态地从表对象中调来的,是表中数据的一个镜像。查询只是告诉Access需要什么样的数据,而Access就会从表中查出这些数据的值,并将它们反映到查询数据表中来罢了,也就是说这些值只是查询的结果。我们刚才选择目标字段就是告诉Access需要哪些表、哪些字段,而Access会把字段中的数据列成一个表反馈给我们。当然在查询中我们还可以运用各种表达式来对表中的数据进行运算生成新的查询字段。
在查询的数据表中虽然不能插入列,但是可以移动列,移动的方法和上一课中在表中移动列的方法是相同的,而且在查询的数据表中也可以改变列宽和行高,还可以隐藏和冻结列。

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