2012年计算机二级Access辅导笔记之建造Access表-Mysql Tutorial-php.cn

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2012年计算机二级Access辅导笔记之建造Access表

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Jun 07, 2016 pm 03:02 PM

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第四章建造 Access表 4.1 Access数据库表概述一,表的组成字段字段的数据类型字段的属性字段的声名二,表的视图设计视图数据表视图数据透视表视图和数据透视图视图 1. 字段字段名称要能够直接,清嚣张的反映信息内容字段命名划定(同样适合于控件和

第四章建造Access表

4.1 Access数据库表概述

　　一,表的组成

　　字段

　　字段的数据类型

　　字段的属性

　　字段的声名

　　二,表的视图

　　设计视图

　　数据表视图

　　数据透视表视图和数据透视图视图

　　1. 字段

　　字段名称要能够直接,清嚣张的反映信息内容

　　字段命名划定(同样适合于控件和对象):

　　长度不能跨越64个西文字符(32个汉字);

　　不能包含句号".",感伤号"!",重音符号和方括号"";

　　不能以空格开首;

　　不能包含节制字符(0～31的ASCII值);;

　　最好确保字段名和Access中已有的属性和其他元素的名称不不异.

　　2. 字段的数据类型

　　合理选择字段的数据类型,可有用的提高数据库效率,并可避免一些错误的发生.

　　例:2002年5月14日

　　日期或时刻

　　日期(Date/Time)

　　货泉值除外

　　用来算术计较的数值

　　数字(Num)

　　注释,声名

　　65 536

　　长文本或文本与数字的组合

　　备注(Memo)

　　地址,电话号码,学号

　　255

　　文鼻橐恺字与文本组合,或不需要计较的数字

　　文本(Text)

　　备注

　　存储空间(字节)

　　合用规模

　　数据类型

　　表4-1 字段的数据类型

　　UNC,URL路径

　　64 000

　　用于超链接

　　超链接(Hyperlink)

　　例:Word,Excel文件

　　1GB

　　用于使用OLE和谈在其它轨范中建树的OLE对象

　　OLE对象(OLEObject)

　　是/否(Yes/No)

　　此类型字段不能更新

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