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sql - TSQL Comparing two Sets

When two sets are given

s1 ={ a,b,c,d} s2={b,c,d,a}

(i.e)

TableA

Item
a
b
c
d

TableB

Item
b
c
d
a

How to write Sql query to display "Elements in tableA and tableB are equal". [Without using SP or UDF]

Output

Elements in TableA and TableB contains identical sets
See Question&Answers more detail:os

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by (71.8m points)

Use:

SELECT CASE 
         WHEN   COUNT(*) = (SELECT COUNT(*) FROM a) 
            AND COUNT(*) = (SELECT COUNT(*) FROM b) THEN 'Elements in TableA and TableB contains identical sets'
         ELSE 'TableA and TableB do NOT contain identical sets'
       END
  FROM (SELECT a.col
          FROM a
        INTERSECT
        SELECT b.col
          FROM b) x 

Test with:

WITH a AS (
  SELECT 'a' AS col
  UNION ALL
  SELECT 'b'
  UNION ALL
  SELECT 'c'
  UNION ALL
  SELECT 'd'),
     b AS (
  SELECT 'b' AS col
  UNION ALL
  SELECT 'c'
  UNION ALL
  SELECT 'd'
  UNION ALL
  SELECT 'a')
SELECT CASE 
         WHEN   COUNT(*) = (SELECT COUNT(*) FROM a) 
            AND COUNT(*) = (SELECT COUNT(*) FROM b) THEN 'yes'
         ELSE 'no'
       END
  FROM (SELECT a.col
          FROM a
        INTERSECT
        SELECT b.col
          FROM b) x 

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