It causes a lot af wierd behaviour when I use APPSQL or Session's Sql object and changing databases while the app is running.
It reads some data from the previously opened database. It is not so good.

So I suggest something like this:

 void Sqlite3Session::Close() {
 	sql.Clear();
 	if (NULL != db) {
+		SessionClose();
 		int retval;
 #ifndef flagNOAPPSQL
 		if(SQL.IsOpen() && &SQL.GetSession() == this)