SQL Server:一张表有 400 列还是 40 表有 10 列?
我使用的是 SQL Server 2005 Express 和 Visual Studio 2008.
I am using SQL Server 2005 Express and Visual Studio 2008.
我有一个包含 400 列的表的数据库.在我不得不在多个数据库之间执行双向同步之前，事情是(几乎可以管理的).
I have a database which has a table with 400 Columns. Things were (just about manageable) until I had to perform bi-directional sync between several databases.
我想知道支持和反对使用 400 列数据库或 40 表数据库的论据是什么?
I am wondering what arguments are for and against using 400 column database or 40 table database are?
该表未规范化，主要由 nvarchar(64) 列和一些 TEXT 列组成.(没有数据类型，因为它是从文本文件转换而来的).
The table in not normalised and comprises of mainly nvarchar(64) columns and some TEXT columns. (there are no datatypes as it was converted from text files).
还有一个表链接到这个表，并且是 1-1 关系(即一个条目与 400 列表中的一个条目相关).
There is one other table that links to this table and is a 1-1 relationship (i.e one entry relates to one entry in the 400 column table).
该表是一个列表文件，其中包含插入"到应用程序中的参数.
The table is a list files that contained parameters that are "plugged" into a application.
期待您的回复.
谢谢
推荐答案
根据你的流程描述，我会从这样的事情开始.该模型被简化，不捕捉历史等等——但是，它是一个很好的起点.注意:参数=属性.
Based on your process description I would start with something like this. The model is simplified, does not capture history, etc -- but, it is a good starting point. Note: parameter = property.
- 设置 是属性 的集合.一个设置可以有多个属性，一个属性只属于一个设置.
- 机器可以有多个设置，一个设置只属于一台机器.
- 属性是特定的类型(温度、运行时间、主轴转速)，某个特定的属性可以有多种输入.
- 度量和特质是属性的类型.度量是一个数字属性，如速度.特征是一种描述性的属性，如颜色或一些文字.
- Setup is a collection of properties. One setup can have many properties, one property belongs to one setup only.
- Machine can have many setups, one setup belongs to one machine only.
- Property is of a specific type (temperature, run time, spindle speed), there can be many properties of a certain type.
- Measurement and trait are types of properties. Measurement is a numeric property, like speed. Trait is a descriptive property, like color or some text.
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