here's a thought...any good?

USE [tempdb]

GO

IF EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[T_VOL_USAGE]') AND type in (N'U'))

DROP TABLE [dbo].[T_VOL_USAGE]

GO

CREATE TABLE [dbo].[T_VOL_USAGE](

[VOL_NAME] [nvarchar](5) NULL,

[NODE_NAME] [nvarchar](5) NULL

) ON [PRIMARY]

GO

INSERT INTO [dbo].[T_VOL_USAGE]([VOL_NAME], [NODE_NAME])

SELECT 'V1', 'B' UNION ALL

SELECT 'V12', 'F' UNION ALL

SELECT 'V3', 'F' UNION ALL

SELECT 'V2', 'C' UNION ALL

SELECT 'V2', 'D' UNION ALL

SELECT 'V3', 'E'

SELECT TV.VOL_NAME,

TV.NODE_NAME

FROM T_VOL_USAGE TV

INNER JOIN (SELECT VOL_NAME

FROM T_VOL_USAGE

GROUP BY VOL_NAME

HAVING ( COUNT(*) = 1 )) A ON TV.VOL_NAME = A.VOL_NAME

INNER JOIN (SELECT NODE_NAME

FROM T_VOL_USAGE

GROUP BY NODE_NAME

HAVING ( COUNT(*) = 1 )) B ON TV.NODE_NAME = B.NODE_NAME