我试了下结果是符合预期的呢，
```sql
CREATE TABLE user_order_price
(
userId UInt64,
orderId UInt8,
price Float64,
sign Int8,
version UInt8
)
ENGINE = VersionedCollapsingMergeTree(sign, version)
ORDER BY (userId,orderId)

INSERT INTO user_order_price VALUES (101, 10000, 100, 1, 1),(101, 10000, 100, -1, 2),(102, 10000, 200, 1, 2)

INSERT INTO user_order_price VALUES (103, 10000, 500, 1, 2)

SELECT
userId,
sum(price * sign) AS avgPrice
FROM user_order_price
GROUP BY userId

```
结果不准确是指哪个位置