首页>
外国专利>
Incremental maintenance of range-partitioned statistics for query optimization
Incremental maintenance of range-partitioned statistics for query optimization
展开▼
机译:增量维护范围划分的统计信息以优化查询
展开▼
页面导航
摘要
著录项
相似文献
摘要
A database management system that manages data in a database includes a query optimizer that performs query optimization based on statistics related to data in the database. The query optimizer incrementally updates the statistics. The query optimizer organizes the statistics related to the data in the database into a statistics tree structure having a root node corresponding to global statistics, internal nodes corresponding to summary statistics of descendant nodes, and leaf nodes corresponding to disjoint data ranges in the database. The query optimizer performs statistics tree transformation operations on the statistics tree structure. The transformation operations transform the statistics tree structure into a form that at least partially minimizes the system resources needed to update the statistics. The query optimizer updates the statistics corresponding to those nodes of the statistics tree structure where a change has occurred in the disjoint data ranges.
展开▼