What do the mysql workbench column icons mean

问题:

In MySQL Workbench, when you edit a table, by each column name, there is a colored diamond. Where can I find a document that explains what each color means?

回答1:

Key: (Part of) Primary Key
Filled Diamond: NOT NULL
Not filled Diamond: NULL
Red colored: (Part of) Foreign key
Blue lined Diamond: Simple attribute (no key)

Can be combined for example:
is a Red colored Key so it's a Primary Key which is also a Foreign Key
is a Yellow (non Red) Key so it's only a Primary Key
is a blue lined filled diamond so it's a NOT NULL simple attribute
is a red colored filled diamond so it's a NOT NULL Foreign Key
is a blue lined not filled diamond so it's a simple attribute which can be NULL
is a red colored not filled diamond so it's a Foreign Key which can be NULL

回答2:

To the left of the column name is an icon that indicates whether the column is a member of the primary key. If the icon is a small key, that column belongs to the primary key, otherwise the icon is a blue diamond or a white diamond. A blue diamond indicates the column has NN set. To add or remove a column from the primary key, double-click the icon. You can also add a primary key by checking the PRIMARY KEY check box in the Column Details section of the table editor.

Source: http://dev.mysql.com/doc/workbench/en/wb-table-editor.html Section: 7.7.1.3.2

回答3:

Using Google, I found this.

http://dev.mysql.com/doc/workbench/en/wb-using-table-tool.html

Is this enough explanation? I'd be happy to help further.