When AllowStreamedConnected is true (the default), then setting the Connected property to true at design time causes this component to automatically establish a database connection when the application starts up. When AllowStreamedConnected is false, the connection must be explicitly opened at runtime, either by setting the Connected property to true, or by calling the Open method. 

Set AllowStreamedConnected to false when using a local test database at design time and a different database at runtime. This allows the application to set the appropriate runtime connection information before opening a runtime connection, without having to explicitly shut down the database connection that is used at design time.