数据库命名规范 一.实体和属性的命名 1.常用单词已经进行了缩写,在命名过程当中,根据语义拼凑缩写即可。注意,由于ORCAL数据库会将字段名称统一成大写或者小写中的一种,所以要求加上下划线 举例: 定义的缩写 Sales: Sal 销售; Order: Ord 订单; Deta
数据库命名规范
一.实体和属性的命名
1.常用单词已经进行了缩写,在命名过程当中,网站空间,根据语义拼凑缩写即可。注意,香港虚拟主机,由于ORCAL数据库会将字段名称统一成大写或者小写中的一种,所以要求加上下划线
举例:
定义的缩写 Sales: Sal 销售;
Order: Ord 订单;
Detail: Dtl 明细;
则销售订单名细表命名为:Sal_Ord_Dtl;
2. 如果表或者是字段的名称仅有一个单词,那么建议不使用缩写,而是用完整的单词。
举例:
定义的缩写 Material Ma 物品;
物品表名为:Material, 而不是 Ma.
但是字段物品编码则是:Ma_ID;而不是Material_ID
3. 所有的存储值列表的表前面加上前缀Z
目的是将这些值列表类排序在数据库最后。
4. 所有的冗余类的命名(主要是累计表)前面加上前缀X
冗余类是为了提高数据库效率,非规范化数据库的时候加入的字段。或者表
5. 关联类通过用下划线连接两个基本类之后,再加前缀R的方式命名,后面按照字母顺序罗列两个表名或者表名的缩写。
关联表用于保存多对多关系。
如果被关联的表名大于10个字母,必须将原来的表名的进行缩写。如果没有其他原因,建议都使用缩写。
举例:表Object与自身存在多对多的关系,则保存多对多关系的表命名为:R_Object;
表 Depart和Employee;存在多对多的关系;则关联表命名为R_Dept_Emp
6.每一个表都将有一个自动ID作为主健,逻辑上的主健作为第一组候选主健来定义,如果是数据库自动生成的编码,统一命名为:ID;如果是自定义的逻辑上的编码则用缩写加“ID”的方法命名。
举例:销售订单的编号字段命名:Sal_Ord_ID;如果还存在一个数据库生成的自动编号,则命名为:ID。
7.所有的属性加上有关类型的后缀,类型后缀的缩写定义见文件《类型后缀缩写定义》,注意,如果还需要其它的后缀,都放在类型后缀之前。
二.关系的命名
关系的命名基本上按照;如有特殊情况,可以灵活处理.
[must/may/can/should][verb/verb+prep][a/many/exatly num][or a/many]的结构命名
三.域的命名
四.触发器的命名
五.有关于默认的几点说明
1. 严格依赖关系的主细表,主表的后缀Main可以不写。
2. 数据类型是文本的字段,类型后缀TX可以不写。
3. 有些类型比较明显的字段,香港服务器租用,可以不写类型后缀。
4. 非常明显的关系,可以不写

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