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Access入门教程7.2怎样为表设置主键

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Jun 07, 2016 pm 04:02 PM

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单击工具栏上的视图按钮切换回表的设计视图开始为表设置主键第五课的课后补充里曾经说过主键是什么设置表的主键非常简单比如要将订单信息表中的订单号字段作为表的主键只要单击订单号这一行中的任何位置将这行设为当前行然后单击工具栏上的

单击工具栏上的视图按钮切换回表的设计视图开始为表设置主键第五课的课后补充里曾经说过主键是什么

设置表的主键非常简单比如要将订单信息表中的订单号字段作为表的主键只要单击订单号这一行中的任何位置将这行设为当前行然后单击工具栏上的主键按钮按钮会凹陷进去在订单号一行最左面的方格中出现了一个钥匙符号表示订单号这一字段成为表的主键了

Access入门教程7.2怎样为表设置主键

用这种方法设置了新的主键以后原来的主键就会消失如果要将表中的多个字段设置成主键要先把鼠标移动到表最左边的方格内当鼠标光标变成一个向右箭头形状时单击鼠标左键将这行选定然后按住键盘上的CTRL键选定其它要设置成主键的行都选好以后单击工具栏上的主键按钮选中的字段都设成主键了如果想取消主键先选中字段然后单击工具栏上的主键按钮这时字段前面的钥匙图标就消失了表示这个字段不再是主键了

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