数据库设计 - 四级亲子关系 [英] Database Design - Four-Level Parent-Child Relationships

问题描述

这可能会有点复杂。我们有一个这样的父子关系：

项目包含许多任务。一个项目也可能有任何数量的修订版本。

这些表的数据库模式如下所示：

 项目：
 ProjectID 
 ProjectName 
 
 ProjectRevisions：
 ProjectRevID 
 ProjectID 
 ProjectRevName 
 
任务：
 TaskID 
 ProjectRevID 
 TaskName 
 HoursToComplete 
  

任务表格是从另一个表格Taskdescriptions填充的，其中包含任务的主列表。

我的雇主也想要subquotes - 意思是个人可以引用自己的努力与主引用分开。每次ProjectRevision发生时，子引文必须重做，所有旧版本和SubQuotes必须保留以备将来参考。

表格模式如何看待？在我看来，这本质上是一个四级列表：一个项目包含一个修订列表，它们都包含一个SubQuotes列表，每个列表都包含一个任务列表。

我可能会反思这个，但是非常感谢任何帮助

解决方案

我的雇主也想要subquotes - 这意味着一个人可以引用自己的努力与主引用分开。每次发生ProjectRevision时，子引文必须重做，所有旧版本的修订版本和SubQuotes必须保留以备将来参考。

表格模式如何？在我看来，这本质上是一个四级列表：一个项目包含一个修订列表，每个列表包含一个SubQuotes列表，每个列表包含一个任务列表。

假设不会有任何一个subquote可能与多个用户有关的情况：

SUBQUOTES 表

• SUBQUOTE_ID ，pk
• 
  
• PROJECT_REV_ID ，fk


• USER_ID ，fk


• [支持列]

我没有看到需要任何其他更改现有数据模型。

This might get a little complicated. Here goes.

Say we have a parent-child relationship like this:

A Project contains many Tasks. A Project may also have any number of Revisions.

And the database schema for these tables look something like this:

Projects:
ProjectID
ProjectName

ProjectRevisions:
ProjectRevID    
ProjectID
ProjectRevName

Tasks:
TaskID
ProjectRevID
TaskName
HoursToComplete

The tasks table is populated from another table, TaskDescriptions, which contains the master list of tasks.

My employer also wants subquotes - meaning an individual can quote his own effort seperate from the master quote. Each time a ProjectRevision takes place, the Subquotes must be redone, and all old Revisions and SubQuotes must be kept for future reference.

How would this look in a table schema? In my eyes, this is essentially a four-level list: A project contains a list of Revisions, which each contain a list of SubQuotes, which each contain a list of tasks.

I may be overthinking this, but any help is greatly appreciated

解决方案

My employer also wants subquotes - meaning an individual can quote his own effort seperate from the master quote. Each time a ProjectRevision takes place, the Subquotes must be redone, and all old Revisions and SubQuotes must be kept for future reference.

How would this look in a table schema? In my eyes, this is essentially a four-level list: A project contains a list of Revisions, which each contain a list of SubQuotes, which each contain a list of tasks.

Assuming there won't be any instances where a subquote could be related to more than one user:

SUBQUOTES table

• SUBQUOTE_ID, pk
• PROJECT_REV_ID, fk
• USER_ID, fk
• [supporting columns]

I don't see any other changes necessary to the existing data model.

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