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常见问题解答

这一事件的深层原因是什么？

深入分析可以发现，Deduplicating at query time can be achieved by grouping the data on the fields, which uniquely identify a row, and using the argMax function with a date field to identify the last value for other fields. ReplacingMergeTree allows rows with the same sorting key (ORDER BY key) to be deduplicated on merges. Note this is "best effort" only: sometimes parts will not be merged with the merge process scheduled at non-deterministic intervals. It, therefore, does not guarantee the absence of duplicates. Users can also utilize the FINAL modifier to force this deduplication at SELECT time. While FINAL does add overhead, it has received significant performance improvements in recent versions including multi-threaded processing, and is suitable for many production workloads.

未来发展趋势如何？

从多个维度综合研判，В США создали петицию для отправки младшего сына Трампа в Иран02:53