can't get results from executequery using FMDB

[izon90]

I created the db with firefox addon sqlite manager. db can be opened. and the query is working in sqlite manager. but i just can't get the results from FMResultSet.

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    // Override point for customization after application launch.
    // Add the navigation controller's view to the window and display.
    NSArray *array = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *path = [array objectAtIndex:0];
    NSString *pathString = [path stringByAppendingPathComponent:@"todo.sqlite"];
    FMDatabase *db = [FMDatabase databaseWithPath:pathString];
    if (![db open]) {
        NSLog(@"cannot connect to database");
    } else
    {
        NSLog(@"successfully!");
    }
    [db open];
    FMResultSet *s = [db executeQuery:@"SELECT * FROM todo"];
    if (!s) {
        NSLog(@"no result set fechted");
    }
	while ([s next]) {
		NSLog(@"%@", [s stringForColumn:@"title"]);
	}    
    [db close];
    
    self.window.rootViewController = self.navigationController;
    [self.window makeKeyAndVisible];
    return YES;
}