了解MySQL Workbench EER图中的箭头提示 [英] understanding arrow tips in MySQL Workbench EER diagram

问题描述

根据此问题，我使用了逆向工程函数来生成Yelp数据集的EER图

有人知道确切的解释方法吗?箭头提示是什么意思，例如，一个带有3个提示和一条线的箭头，一个带有2条平行线的箭头.然后有一些没有任何提示.

然后，箭头进入或离开表格的点是什么意思，例如，将笔尖表格留在文本周围并输入计数周围的签入表格，还是无关紧要?

我在其中注意到的另一个细节是，黄色灯泡可能是主键，而红色菱形可能是外键.但是从图中仍然看不到彩色符号和箭头是如何连接的.

解决方案

基数和序数:

来源:https://www.lucidchart.com/pages/ER图符号和含义

I used the reverse-engineer function to generate an EER diagram of the Yelp dataset as per this question here. It looks like this:

Does anyone know exactly how to interpret it? What do the arrow tips mean, eg the one with 3 tips and a line, the one with 2 parallel lines. Then there are some without any tips.

Then, does the point at which the arrow enter or leave a table mean anything, eg one leaves the tip table around text and enters the checkin table around count, or is that irrelevant?

Another detail I noticed in there is that the yellow lightbulb is probably a primary key and the red diamond, a foreign key. Still can't see from the diagram however how the coloured symbols and arrows connect.

解决方案

Cardinality and ordinalitiy:

Source: https://www.lucidchart.com/pages/ER-diagram-symbols-and-meaning

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