Du måste convert
och Cast
Date
och använd den sedan i BETWEEN
klausul. Prova detta.
SELECT Con_Consult_Date
FROM Consultation
WHEREE CAST(CONVERT(CHAR(10), CONVERT(DATETIME, Con_Consult_Date, 105), 101) AS DATE)
BETWEEN CAST(CONVERT(CHAR(10), CONVERT(DATETIME, '01-01-2013', 105), 101) AS DATE)
AND CAST(CONVERT(CHAR(10), CONVERT(DATETIME, '31-12-2013', 105), 101) AS DATE)
GO