端点选择、接口端点和订阅缓存还未使用,因此我们当前将不优化它们的参数。
The endpoint selection, interface endpoints, and subscription caches are not yet used, so we will not tune their parameters at this time.
一旦理解了自己的选择,就可以通过调整OPTCOMPIND参数,或者通过添加查询指示或索引,来影响优化器,从而选择最佳的查询执行计划。
Once you understand your options, you can influence the optimizer to select the best query execution plan, either by adjusting the OPTCOMPIND parameter or by adding query directives or indexes.
正如我们在本文讨论的,如果sql语句中存在主机变量或参数标记,那么DB 2优化器可能会选择一个次优化的存取计划。
As we've discussed in this article, the DB2 optimizer may choose a sub-optimal access plan when there are host variables or parameter markers in the SQL statement.
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