Determine whether a field has an index and, if so, whether the query can efficiently use the index.
您要决定字段是否拥有索引,如果是的话,那么查询是否能够有效地使用索引。
Using a stored procedure as query subject input has the advantage that no unnecessary tables or views are created in the database.
使用存储过程作为查询主题输入有一个好处,那就是不需要在数据库中创建不必要的表或视图。
Now consider the difficulties inherent with a query on a connector in which each folder in the root folder has to be logged into separately.
现在,请考虑:当必须分别登录连接器根文件夹中的每一个文件夹时,在连接器上所进行的查询会有什么固有的困难。
This has several implications for the design of a query language.
这对查询语言的设计具有多种含意。
The weighing machine is a component of a production line, which has methods to query the type of sweet being produced and the size of the jars being filled.
称重机是生产线的一个组件,它具有一些方法,查询所生产的糖果类型以及所填装的罐子规格。
The query has a WHERE clause that will only fetch the most recent values.
这个查询有一个WHERE 子句,用于过滤出最近的值。
The STAFF table has grown to over a million records, and the query is therefore taking longer than it took in the past.
staff表已经增长到一百万条记录以上,因此这个查询花费的时间比以前长了。
A summary table stores data that has been aggregated in a way that answers a common (or resource-intensive) business query.
汇总表存储以回答常见(或资源密集型)业务查询的方式汇总的数据。
Figure 7 illustrates the typical usage patterns and enabled actions after an initial set of data has been retrieved or a refresh made of a follow-up query.
图7展示了检索到一组数据或者经后续查询进行了刷新之后,通常的使用模式和支持的操作。
After the connection has been created, it creates a statement and executes a query.
在创建连接之后,将创建一条语句并执行一个查询。
Now that a query has been set up and the counters have been added, it is possible to begin gathering performance data.
既然设置了查询和添加了容器,现在就可以开始收集性能数据了。
Once a reply to a database query has been returned, then the reply, the intermediate state, and the query itself are no longer needed.
一旦返回数据库查询的响应之后,就不再需要回复、中间状态和查询本身。
WebSphere Process Server has a feature called Query Table that improves performance for large deployments.
WebSphereProcessServer有一个称为查询表的特性,它可以提高大型部署的性能。
Once the MYSELECTS view has been created, we can construct a query that retrieves data from both this view and the SYSCAT.TABLES view.
创建MYSELECTS视图之后,我们可以构造一条查询,从该视图和SYSCAT. TABLES视图中检索数据。
You can confirm that the database has in fact been updated by performing a select query on the cachetbl as you can see in Figure 1.
通过对cachetbl执行一个选择查询,可以确认数据库实际上已经更新,如图1所示。
If a query has a function template in a predicate or a select list, the function template must be part of the materialized query table.
如果查询在谓词或选择列表中具有一个函数模板,那么该函数模板必须是物化查询表的一部分。
One example of implementing a prompt in a model is shown below in which the time dimension query subject has a filter added with prompt syntax.
以下就是在模型中实现提示的例子,其中时间维度查询主题通过提示语法添加了一个过滤。
And they only appear when the database administrator runs a query profiler on your system when it has performance problems.
并且它们只有在数据库管理员在系统具有性能问题时在系统上运行查询剖析器时才会出现。
When you provide more detailed search conditions by having more predicates in a query, the optimizer has a chance to make better choices.
当通过在查询中设置更多谓词来提供更详细的搜索条件时,优化器就有机会作出更好的选择。
Each tag has a node attribute that takes a query expression describing a single model node in the DOM.
每种标记都有一个节点属性,该属性携带一个描述DOM中单一模型节点的查询表达式。
The technique described here can be applied to any database, provided the database has tools similar to DB2 for displaying and cancelling a given query.
这里所介绍的技术能适用于任何数据库,只要这个数据库使用类似于db2的工具来显示和取消一个给定查询。
Recently, a new standards-based XML query language has been published.
最近,一种新的、基于标准的XML查询语言已经发布。
Query output has a fixed number of columns, with each row filling in values for every fixed column.
在查询输出中,列的数量是固定的,每行填入了每个固定列的值。
A runtime library has no opportunity to analyze a program and structure the query evaluations in an optimal manner.
运行时库没有机会分析程序并以最优的方式构建查询计算。
It has all the methods you need to connect to a UDDI registry, execute a query, and process the results.
它有连接到UDDI注册表、执行查询和处理结果所需要的所有方法。
Here the original query is comparing a string to a number but in the modified query, explicit type-casting has been done.
原来的查询比较一个字符串和一个数字,但是在修改后的查询中执行了显式的类型转换。
File system caching has a significant impact only on query Q1 which retrieves all documents without any predicate evaluation.
文件系统缓存仅对查询Q1(检索全部文档,无谓词运算)有较大影响。
JPA also has a fully functional query language that can work against an object model.
JPA还拥有可以用于对象模型的全功能查询语言。
A query is often slow because it has no index or an inefficient index.
查询很慢,因为没有索引或者索引不足够。
If the master query table has a large volume of data, perhaps millions of rows, then there might be an unacceptable amount of queries issued to the database table on the detail side.
如果主查询表拥有大量数据,比如数百万行,那么向明细端上的数据库表发出的查询量可能难以接受。
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