CREATE TABLE my_table (
  `name` String,
  `id` UInt64,
  `amount` Int64,
  `currency` String,
  `created_at` DateTime
) ENGINE = ReplicatedSummingMergeTree(...)
ORDER BY
  (
    name,
    id,
    created_at,
    currency
  )

SYSTEM SYNC REPLICA default.test_sync
Received exception from server (version 20.8.12):
Code: 236. DB::Exception: Received from localhost:9000. DB::Exception: Log pulling is cancelled.
0 rows in set. Elapsed: 0.002 sec.

CREATE TABLE test
      (
        user_id          UInt64,
        amount           Int64
      )
      ENGINE = SummingMergeTree()
      ORDER BY (user_id)

      select uniqExact(user_id) from my_table => 70k

      insert into test (user_id, amount) select user_id, amount from my_table

      select uniqExact(user_id) from test => 60k

Если значения во всех столбцах для суммирования оказались нулевыми, то строчка удаляется.

CREATE TABLE summtt
(
    `key` UInt32,
    `value` UInt32
)
ENGINE = SummingMergeTree()
ORDER BY key 

INSERT INTO summtt Values(1,1),(1,2),(2,1),(3,0)

SELECT *
FROM summtt
FINAL

┌─key─┬─value─┐
│   1 │     3 │
│   2 │     1 │
└─────┴───────┘