DROP TABLE IF EXISTS test.aggregating; CREATE TABLE test.aggregating (d Date DEFAULT '2000-01-01', k UInt64, u AggregateFunction(uniq, UInt64)) ENGINE = AggregatingMergeTree(d, k, 8192); INSERT INTO test.aggregating (k, u) SELECT intDiv(number, 100) AS k, uniqState(toUInt64(number % 100)) AS u FROM (SELECT * FROM system.numbers LIMIT 1000) GROUP BY k; INSERT INTO test.aggregating (k, u) SELECT intDiv(number, 100) AS k, uniqState(toUInt64(number % 100) + 50) AS u FROM (SELECT * FROM system.numbers LIMIT 500, 1000) GROUP BY k; SELECT k, finalizeAggregation(u) FROM test.aggregating FINAL; OPTIMIZE TABLE test.aggregating; SELECT k, finalizeAggregation(u) FROM test.aggregating; SELECT k, finalizeAggregation(u) FROM test.aggregating FINAL; DROP TABLE test.aggregating;