DECLARE @tblsplit TABLE (Category char, U_Name varchar(25))

INSERT INTO @tblsplit (Category, U_Name) VALUES ('H', 'Пупкин Василий')
INSERT INTO @tblsplit (Category, U_Name) VALUES ('H', 'Маша Иванова')
INSERT INTO @tblsplit (Category, U_Name) VALUES ('L', 'Федя Петров')
INSERT INTO @tblsplit (Category, U_Name) VALUES ('L', 'Леня Голубков')

SELECT 
CASE WHEN Category = 'H' THEN Category ELSE '' END as 'Сливки общества', 
CASE WHEN Category = 'L' THEN Category ELSE '' END as 'Простые смертные',
U_Name 
FROM @tblsplit