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You are given a table, Functions, containing two columns: X and Y. Two pairs (X1, Y1) and (X2, Y2) are said to be symmetric pairs if X1 = Y2 and X2 = Y1. Write a query to output all such symmetric pairs in ascending order by the value of X. List the rows such that X1 ≤ Y1. Sample Input Sample Output 20 20 20 21 22 23 SELECT F1.X, F1.Y FROM Functions F1 JOIN Functions F2 ON (F1.X = F2.Y AND F1.Y ..