DECLARE @PARAMETERS TABLE ( PARAMETER_NAME VARCHAR(5))

INSERT INTO @PARAMETERS VALUES ('A')
INSERT INTO @PARAMETERS VALUES ('B')
INSERT INTO @PARAMETERS VALUES ('C')
INSERT INTO @PARAMETERS VALUES ('D')
INSERT INTO @PARAMETERS VALUES ('E')

SELECT * FROM @PARAMETERS;

WITH OrderedParams AS (
SELECT
PARAMETER_NAME,
ROW_NUMBER() OVER (ORDER BY PARAMETER_NAME) AS rn
FROM @PARAMETERS
),
Masks AS (
SELECT TOP (POWER(2, (SELECT COUNT(*) FROM @PARAMETERS)) - 1)
ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) AS mask
FROM sys.objects
),
Combinations AS (
SELECT
STRING_AGG(p.PARAMETER_NAME, '-') WITHIN GROUP (ORDER BY p.rn) AS combination,
COUNT(*) AS combination_size
FROM Masks m
JOIN OrderedParams p
ON (m.mask & POWER(2, p.rn - 1)) > 0
GROUP BY m.mask
)
SELECT
combination,
combination_size
FROM Combinations
ORDER BY combination_size, combination;



WITH OrderedParams AS (
SELECT
parameter_name,
ROW_NUMBER() OVER (ORDER BY parameter_name) - 1 AS bit_pos
FROM @Parameters
),
Masks AS (
SELECT TOP (POWER(2, (SELECT COUNT(*) FROM @Parameters)) - 1)
ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) AS mask
FROM sys.objects
),
Combinations AS (
SELECT
m.mask,
STRING_AGG(p.parameter_name, '-')
WITHIN GROUP (ORDER BY p.bit_pos) AS combination,
COUNT(*) AS combination_size
FROM Masks m
JOIN OrderedParams p
ON (m.mask & POWER(2, p.bit_pos)) > 0
GROUP BY m.mask
)
SELECT
c1.combination AS Combination1,
c2.combination AS Combination2,
c1.combination_size AS Size1,
c2.combination_size AS Size2
FROM Combinations c1
JOIN Combinations c2
ON c1.mask < c2.mask
AND (c1.mask & c2.mask) = 0
ORDER BY Size1, Size2, Combination1, Combination2;