关于 Access 数据库中的数据类型与 Access 项目中的数据类型的不
Microsoft Access 提供两种字段 数据 类型 (字段 数据 类型 :决定可以存储哪种 数据 的字段特征。例如, 数据 类型 为文本的字段可以存储由文本或数字字符组成的 数据 ,而数字字段只能存储数值 数据 。) 以存储文本或数字,或两者的组合:文本和备注。
Microsoft Access 提供两种字段数据类型 (字段数据类型:决定可以存储哪种数据的字段特征。例如,数据类型为“文本”的字段可以存储由文本或数字字符组成的数据,而“数字”字段只能存储数值数据。)以存储文本或数字,或两者的组合:“文本”和“备注”。
使用“文本”数据类型存储如名称、地址和任何不需计算的数字,如电话号码、部件编号或者邮政编码。“文本”字段能存储最多 255 个字符,但默认字段大小是 50 个字符。“字段大小”属性控制可以输入“文本”字段的最大字符个数。
如果需要存储超过 255 个字符,应使用“备注”数据类型。“备注”最多可以存储 65,536 个字符。如果要存储带格式文本或长文档,可以创建 OLE 对象字段代替“备注”字段。
“文本”和“备注”数据类型存储输入到一个字段中的值;不存储字段中没用的部分的空白字符。
可以对“文本”或者“备注”字段进行分组和排序,但 Access 只使用“备注”字段的前 255 个字符进行分组和排序。

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