aggregation queries

• 聚集查询

aggregation queries的用法和样例：

例句

1. Based on randomizing techniques, this paper discussed how the sketch-based approach estimates approximate answers to aggregate queries.
   摘要讨论了基于草图的复杂聚集查询的近似处理算法。
2. HierPrefixCube retains advantages on computation and organization of PrefixCube, and it can directly support aggregate queries on levels of the dimension hierarchy.
   它不仅保留了前缀立方在计算和组织结构上的优点，又能直接和充分支持维层次级的聚集查询。