In a SDLC, creating a database model diagram is an important step that needs to be taken to achieve the following

- Create a clear visualization of the Database for the system which makes the database understanding pretty easier

- It helps in derive out the classes required to be created by just looking into the database modeling diagram in depth

If you are not able to buy the paid tool for UML modeling such as rational rose etc., it’s still achievable through Microsoft Visio. Following are the steps that need to be performed to create a model diagram from an existing MySQL database in Microsoft Visio which is called as Reverse Engineering

- First of all, download the ODBC driver for MySQL from the location http://dev.mysql.com/downloads/connector/odbc/5.1.html. Download the installable by selecting the appropriate one based on  your machine configuration (32 bit or 64 bit)

- Install the mysql connector

- After installation, open visio

- Go to File->New->Database->Database Model

- From Database Menu, select Reverse Engineer

- On the Create New Datasource screen displayed, click on User Data Source

- Provide a datasource name

- Select the mysql connector driver, click on Next

- Click Finish and your new datasource would be added and would come as selected

- Click on Next

- Enter the valid username and password to create the connection using the datasource

- Select Object Type to reverse engineers

- You would be asked to select the database

- On selecting database, tables would be displayed

- Select the tables you want to create the datamodel for

- On selecting the tables, you would be asked to create the model with shape or without shape

- I select the shaped one and the model is generated

It’s really a helpful tool for the beginner to start creating the Database Modeling Diagram from an existing Database