Remove rows having swapped column values in SQL Server

I have a table like + ----------------------- + | RowID | FromCol | toCol | + ----------------------- + | 1 | a | b | | 2 | b | c | | 3 | c | d | | 4 | c | b | | 5 | b | a | + ----------------------- + I would like to remove the rows that has FromCol --> ToCol same value as ToCol --> FromCol For eg. RowID 1 is a-->b and RowID 5 has b-->a so rowID 5 should be removed. Similarly RowID 4 should be removed because it has a swapped value like RowID 2. My expected result Table is: + ----------------------- + | RowID | FromCol | toCol | + ----------------------- + | 1 | a | b | | 2 | b | c | | 3 | c | d | + ----------------------- + Above can be achieved by the below query   select t1.* FROM dbo.MyTest t1 WHERE (SELECT COUNT(t2.rowid) FROM dbo.MyTest t2 WHERE t2.toCol= t1.fromCol AND t2.fromCol= t1.toCol AND t1.rowid> t2.rowid) = 0