Breaking the column distribution per fragment allows for statistics management at the fragment level.
按照片段打断列分布将允许在片段级别上实现统计管理。
Without correct column distribution statistics, DB2 may not have enough information to make the best choice when choosing an access path to the data-especially if data is heavily skewed.
在选择数据的访问路径时,如果没有正确的列分布统计数据,DB 2可能没有足够的信息来做出最佳的选择,尤其是如果数据出现严重误差。
On the other hand, some distribution statistics, such as column frequency, have never been collected.
另一方面,有些分布统计数据(如列频度)并未收集。
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