Access入门教程7.5怎样设置字段的属性（二）
有效性规则 是为了检查字段中的值是否有效 可以在该字段的 有效性规则 框中输入一个表达式 Access会判断输入的值是否满足这个表达式 如果满足才能输入 输入违反该规则的字段值就无法将值输入到表中 并会提示我们不能输入与有效性规则相悖的数值 当然我们也可
在Access中
索引属性是表中一个重要的属性
最后一个是
结束语
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