Opening a connection

Opening a connection either via the Open menu item or double-clicking on the connection node will update the DB Browser pane displaying the tables, views and stored-procedures in the database corresponding to that connection (see Figure 1.4).


Figure 1.4. DB Browser pane

The DB Browser pane is utilized for viewing the database objects of the currently active connection, and more importantly to drag-drop such objects into the Relations pane.

Essentially, this pane will display the currently open database with static folders Tables, Views and Stored Procedures, respectively containing all the existing tables, views and stored-procedures in that database. These objects being nodes in respective Tables, Views and Stored Procedures folders, will have their field or parameter structures as child-nodes.

At this point, we should observe that the Connections pane is used to open a database connection and with the help of the DB Browser pane to view the content of that database. Moreover, for the currently active database we may use the Connections pane to open or create a particular query, in which case this query will be displayed via the Relations, Columns and SQL panes. Observe also that only one query may be opened or viewed at a time, and that the query builder has some sort of SDI (Single Document Interface) user interface.

More precisely, for each project instance of the ELS-QB query builder, the GUI behaves in SDI manner. However, a programmer may use the ELS-QB component in a way so that each ELS-QB instance may be controlled by some MDI application, with the MDI child windows being query builder projects (see the sample applications for an example).