Universal Reverse Engineering

You can reverse engineer a number of databases, such as Sybase ASA and ASE, Oracle, Informix, MSSQL and others. This means that you can extract theirs tables, attributes, relationships, indexes and other object. This is possible with the Universal Reverse Engineering tool, which connects to a number of databases through OLEDB or ODBC link. So, to reverse engineer a particular database, you need corresponding OLEDB provider, or ODBC driver. In most cases, such libraries are installed in the system by database client applications.

To reverse engineer a database through OLEDB or ODBC link:

Choose File | Reverse Engineer | Universal Reverse Engineering.
If the currently opened diagram already contains some objects, the following dialog will appear:

It requests you to create a new diagram to place the reversed objects or use the currently opened diagram.
Click Yes to create a new diagram, No to use the current diagram. Cancel to cancel reverse engineering.
Select Do not show this dialog again to prevent the showing of this dialog again.
The Universal Reverse Engineering tool will be shown.
First, provide full OLEDB connection string in the Connection tab.

Click on the ... button to call the standard system Data Link Properties dialog, which helps you to build OLEDB connection string:

To use ODBC drivers, click on the Microsoft OLE DB Provider for ODBC Drivers. To use the native OLEDB provider, click on the appropriate item in the list.
Browse through tabs to set other tabs and connection properties. Click on the Help button on the bottom of dialog to learn more about OLEDB connections.
Click on the OK button to store the data link properties in the Connection string field of the Universal Reverse Engineering dialog.
You can set reverse engineering options in the Option tab:

Build references
This option enables extracting foreign keys from the database and creating the appropriate references in your diagram.

Automatically rebuild references when no reference is reversed
If there are no physical references extracted, it is possible to build them from logical structure of the database.
Enabling this feature leads to automatic reconstruction of references. Such reconstruction works by the following scheme: each column of a table is being compared with all primary keys of other tables, and if the column name and data type match one of the primary keys, a reference between the source column and the key column will be created.
This option available for modification only if Build references is checked.

Tables in a Diagram row
This option determines how reversed tables will be disposed on the diagram.
Reversed tables will be placed on the diagram in rows with equal distance, this option determines how many tables at most will be in one row.
In the Selection tab of the Universal Reverse Engineering tool you can choose tables you want to reverse engineer.

Check on a checkbox near the table to enable its reverse engineering.
Pay attention to the Select All and Deselect All button on the tab, they allow you to select/deselect all tables in the list.
Click OK to start the database reverse engineering process. The Output -> Reverse docking window will display the state of the process.
The reversed database objects will be placed on your diagram.