### JoinDB Custom Control

The JoinDB custom control coordinates database queries to multiple databases, including:

- Employee Information database—used by the Employee Information component (described in Viewing Employee Information)
- Office Equipment Order Management database—used by the Office Equipment Order Management component (described in Ordering Office Equipment)

The JoinDB custom control is employed by the CheckStatus action defined in the Order portlet page flow, as described in Order Portlet.

The JoinDB custom control and related files are stored within the JoinDB folder in the e2ePortal application, as shown in the following figure.

Files for the JoinDB Custom Control

The following table describes the contents of the JoinDB folder.

JoinDB Custom Control File Descriptions

File | Function
--- | ---
JoinDBImpl.jcs | Defines the implementation code for the custom control.
JoinDB.java | Defines the public interface for the custom control. This file is automatically generated by WebLogic Workshop.
OrderStatus.java | Defines the OrderStatus() method used to merge order tracking information (retrieved from the Office Equipment Order Management database) with employee information (retrieved from the Employee Information database). This method is used by the custom control.
UsersDBControl.jcx | Database control file that defines the database calls used to retrieve employee information. This control is defined in detail in Viewing Employee Information.