What do the mysql workbench column icons mean in ER Diagram?

Question

Can any one help me in explaining about the icons in the ER Diagram of Database created in MySQL Workbench.

• Blue Diamond (Filled);
• Blue Diamond (unfilled);
• Red Diamond, et cetera;
  Thanks!

Answer 1

I've found these resources on MySQL's website:

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

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.

In addition to the text above, a red diamond indicates a Foreign Key association.

To answer your question:

• Blue Diamond (Filled) = indicates NOT NULL
• Blue Diamond (unfilled) = indicates NULL
• Red Diamond, et cetera = indicates a foreign key {filled: NOT NULL, unfilled: NULL}