The Connections tab displays the connections to the database. At any time, multiple connections may be running. Some may be stopped at a breakpoint, and others may not.
The source code window displays the state for a single connection. To switch connections, double-click a connection on the Connections tab.
A useful technique is to set a breakpoint so that it interrupts execution for a single user ID. You can do this by setting a breakpoint condition of the following form:
CURRENT USER = 'user-name'
The SQL special value CURRENT USER holds the user ID of the connection.
For more information, see Editing breakpoint conditions, and CURRENT USER special value.