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CREATE TABLE t ( product char, position char, count INT ); INSERT into t values ('onion', 'in', 10), ('onion', 'out', 3), ('cucumber', 'in', 30), ('carrot', 'in', 23), ('onion', 'out', 7), ('cucumber', 'out', 12), ('potato', 'in', 80), ('onion', 'in', 21), ('cabbage', 'in', 35), ('carrot', 'out', 12), ('cabbage', 'out', 3), ('mango', 'in', 25), ('onion', 'out', 3), ('potato', 'out', 10), ('apple', 'in', 45), ('cabbage', 'out', 20), ('cucumber', 'in', 81), ('apple', 'out', 7), ('mango', 'in', 13), ('orange', 'in', 75), ('orange', 'out', 75); SELECT product, SUM(count * (CASE WHEN position = 'in' THEN 1 ELSE -1 END)) AS result FROM t GROUP BY product HAVING result != 0;