Thus, the way you write the XMLEXISTS predicate can affect the join order in these previous versions of DB2.
因此,编写xmlexists谓词的方式可以影响以前的DB 2版本连接顺序。
The optimizer can use its knowledge of the appliance components to determine the best join order in a complex join.
优化器可以利用其有关设备组件的知识,确定复杂联接操作中的最佳联接顺序。
Relational guidelines such as join, MSJOIN, NLJOIN, and HSJOIN can be used to specify the join order and the join type.
关系准则,比如join、MSJOIN、NLJOIN和HSJOIN都可以用来指定连接顺序和连接类型。
Using views in a SELECT statement can restrict the join order of the tables and limit the query optimizer's choices when considering access plans.
在select语句中使用视图,可以限制表的连接顺序,同时也限制查询优化器在考虑访问计划时的选择。
For example, in debugging problems where you suspect the join order is not optimal, it can be useful to gather counts for different join combinations.
比方说,在调试怀疑连接顺序不是最优的问题时,针对不同的连接组合收集计数可能会有帮助。
As join operation to relational database, structural join order selection is at the heart of query optimization in an XML database.
和关系数据库中的连接运算一样,结构连接顺序的选择是XML数据库查询优化的核心。
Often the join order of a query will greatly determine the query execution performance, since it is more efficient to filter rows as early as possible.
通常,查询的连接顺序很大程度上决定了查询的执行性能,因为越早地过滤行,效率越高。
As part of the transformation, the optimizer also determines the correct table join order, rewrites expressions, and eliminates any redundancy from the SQL.
作为转换的一部分,优化器还决定正确的表联接顺序,重写表达式,并从SQL中消除任何冗余。
You can define guidelines that influence only a few attributes of an execution plan, such as index specification for a certain table in the query or join order for a pair of tables.
可以定义那些只影响执行计划的某些属性的准则,比如查询中的某个表的索引说明,或者一对表的连接顺序。
Join order directives that force optimizer to join tables in the designated order.
连接次序指示,强制优化器按照指定次序连接表。
Join order directives that force optimizer to join tables in the designated order.
连接次序指示,强制优化器按照指定次序连接表。
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