为了实现星型连接查询的最佳执行计划,优化器在适当的时候会考虑星型连接优化,并根据成本因素来决定星型连接计划。
The optimizer considers star join optimization when appropriate and decides on star join plan based on cost considerations in order to come up with best execution plan for a star join query.
当评估查询执行计划时,优化器计算并比较每种连接方法的成本,然后选择要使用的最佳方法。
The optimizer calculates and compares the costs of each join method and selects the best one to use when evaluating query execution plans.
更新统计数据是最重要的管理任务之一,它确保优化器选用最佳的查询执行计划。
Updating statistics is one of the most important administrative tasks that ensure the optimizer picks optimum execution plans for your queries.
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