CREATE DATABASE IF NOT EXISTS test; DROP TABLE IF EXISTS test.decimal_sum; CREATE TABLE test.decimal_sum ( date Date, sum32 Decimal32(4), sum64 Decimal64(8), sum128 Decimal128(10) ) Engine = SummingMergeTree(date, (date), 8192); INSERT INTO test.decimal_sum VALUES ('2001-01-01', 1, 1, -1); INSERT INTO test.decimal_sum VALUES ('2001-01-01', 1, -1, -1); OPTIMIZE TABLE test.decimal_sum; SELECT * FROM test.decimal_sum; INSERT INTO test.decimal_sum VALUES ('2001-01-01', -2, 1, 2); OPTIMIZE TABLE test.decimal_sum; SELECT * FROM test.decimal_sum; INSERT INTO test.decimal_sum VALUES ('2001-01-01', 0, -1, 0); OPTIMIZE TABLE test.decimal_sum; SELECT * FROM test.decimal_sum; drop table test.decimal_sum;