SQL - Date Math question

From: Alex <oradeveloper_at_yahoo.com>
Date: 8 Mar 2005 05:34:14 -0800
Message-ID: <1188063f.0503080534.2f9d4ec7@posting.google.com>

I have two SQL statements:

Statement #1

SELECT	CARRIER_REFERENCE_NUMBER,
        CURRENT_FLEET_SIZE,
	trunc(Fleet_Size_Effective_From_Date),
	trunc(Fleet_Size_Effective_To_Date)
	FROM CAPS.CARRIER_FLEET_SIZE_HISTORY	
	WHERE 	CARRIER_REFERENCE_NUMBER = 481
	AND	trunc(Fleet_Size_Effective_TO_Date) >= 
TO_DATE('24-FEB-2003')		AND	trunc(Fleet_Size_Effective_From_Date) <=
TO_DATE('24-FEB-2004')
	ORDER BY CARRIER_REFERENCE_NUMBER,
                 Fleet_Size_Effective_From_Date,	
		 Fleet_Size_Effective_To_Date,
		 CURRENT_FLEET_SIZE 
						
******************************************************************************

Statement #2                                                 

SELECT	CARRIER_REFERENCE_NUMBER,
	CURRENT_FLEET_SIZE,
	TRUNC(Fleet_Size_Effective_From_Date) AS START_DATE,
	TRUNC(Fleet_Size_Effective_To_Date) AS END_DATE 
	FROM CAPS.CARRIER_FLEET_SIZE_HISTORY	
	WHERE 	CARRIER_REFERENCE_NUMBER = 481
	AND TO_DATE(Fleet_Size_Effective_TO_Date,'DD-MON-YYYY') >= 

TO_DATE(ADD_MONTHS(SYSDATE, -12),'DD-MON-YYYY') AND TRUNC(Fleet_Size_Effective_From_Date) <= TO_CHAR(SYSDATE,'DD-MON-YYYY')

	ORDER BY CARRIER_REFERENCE_NUMBER,
		 Fleet_Size_Effective_From_Date,	
		 Fleet_Size_Effective_To_Date,
		 CURRENT_FLEET_SIZE 

Statement #1 returns 13 records....statement #2 returns 5 records.

Both Fleet_Size_Effective_TO_Date and Fleet_Size_Effective_From_Date are of a DATE datatype. I am trying to restrict the query to the sysdate as an end date, and sysdate - 12 months as a start date. What's wrong with my date math?
Any input into this would be greatly appreciated. Received on Tue Mar 08 2005 - 07:34:14 CST