For the above query, the predicate on t1.pending is unknown.
在上面的查询,t1 .pending断言的值是未知的。
For example, a Blast data source needs an equality predicate on the BlastSeq column.
例如,一个Blast数据源需要blastseq列上的一个等于谓词。
Both indexes defined above are eligible to evaluate the XMLEXISTS predicate on the customer name.
上面定义的两个索引都适合用于客户姓名上的xmlexists谓词的计算。
The company's plan to increase production is predicate on the grow demand for computer product.
公司增加生产的计划基于不断增涨的电脑产品需求量。
Although unwieldy, this does correctly match the predicate on the server and return the expected value.
虽然有些笨拙,但是这的确能正确地匹配服务器上的谓词,并返回预期的值。
It evaluates the predicate on "title" and, if the predicate is satisfied, extracts the "authors" element.
它将在“title”上计算谓词,如果满足谓词,则提取“authors”元素。
DB2 can use an index defined on a single relational column to answer any equality or range predicate on this column.
DB 2可以使用定义在单个关系列上的索引来响应此列上的任何等式谓词或范围谓词。
In order to use this technique, the SQL must provide a predicate on the first key column of the partitioning index.
为了使用这种技术,SQL必须提供分区索引的第一个键列上的一个谓词。
Note that the join predicate on the author ID does not contain a literal value that would indicate the data type of the comparison.
请注意,authorID上的连接谓词没有包含文字值,该文字值将表明比较的数据类型。
In contrast to the previous queries, the following query adds a predicate on the message element using the contains XQuery function.
与前面的查询相反,以下查询使用containsXQuery函数在message元素上添加一个谓词。
Another potential problem is the local predicate on the table reference CUST_ORDER_HEADER (COHE) in the inner sub-query (see also in Figure 9).
另一个潜在问题是内部子查询中CUST_ORDER_HEADER (COHE)表引用上的本地谓词(见图9)。
Of course, in many queries, you'll see that where isn't doing more than XPath; it's just moving the predicate on an XPath to a different place.
当然,您将看到在很多查询中where并不比xpath强,只不过把XPath的谓词转移了一个地方。
It is useful when a table has a finite set of values for the fragment key (or partitioning key) and queries on the table have an equality predicate on the fragment key.
如果表格有一定数量的片段键(或者分区键)值,而且在片段键上有同等谓词的表格上查询时,它会很有用处。
Since Query 1 expresses the join predicate on the books table, DB2 9.1 and 9.5 perform a table scan on authors and then use the index AUTHORIDX1 to probe into the books table.
由于查询1表达了books表中的连接谓词,所以DB 2 9.1和9.5执行一个扫描authors的表,然后使用索引authoridx 1查找books表。
In the first two queries, the filtering predicate is expressed on the constructed XML.
在前两个查询中,过滤谓词是在构造的XML上表达的。
For example, this might happen when two ore more of the tables in the MQT have a referential integrity relationship defined and the join predicate is on their primary key - foreign key columns.
例如,当MQT中的两个或多个表定义了引用完整性关系并且联结谓词在它们自己的主键-外键列上时,就会出现这种情况。
With the step-by-step analysis on statistics, predicate, and index, the performance of the problem query is improved significantly.
通过对统计数据、谓词和索引的逐步分析,问题查询的性能大幅提升。
A high value here can indicate excessive table scans that can be prevented by creating indexes on the predicate columns.
如果该值很大,表示可以通过对谓词列创建索引来避免多余的表扫描。
The query annotation for the predicate shows that there are 273 distinct values on column PRODUCT_NUMBER.
谓词的查询注释显示在列 PRODUCT_NUMBER 上有 273 个不同的值。
Here we are using the two indexes, and we have the same predicate, this time on the index scan numbered 3 in the plan.
在这里我们使用了两个索引,并且有同样的谓词,这一次针对计划中编号为3的索引扫描。
When the evaluate uncommitted behavior is enabled for your DB2 environment, you should be aware that predicate evaluation may occur on uncommitted data.
当您的DB 2环境中启用了evaluateuncommitted行为时,您应该清楚,谓词计算可能发生在为提交的数据上。
Before moving on to pseudo columns and more complex examples, I want to briefly explain where the where predicate of an Oracle recursion needs to be placed.
在讨论伪列和更复杂的例子之前,我想简要地解释一下Oracle中递归的WHERE谓词应该放在哪里。
XQuery also builds on XPath, meaning everything you've learned about nodes, predicate matching, and how elements and attributes relate to each other applies to XQuery.
XQuery也构建在XPath 之上,这意味着您所知道的关于节点、谓词匹配,以及元素和属性如何彼此关联等所有内容都适用于 XQuery。
In the first query, the filtering predicate is expressed on the CHAR column "Zip" generated by the XMLTABLE function.
在第一个查询中,过滤谓词是在由xmltable函数生成的char列“Zip”上表达的。
If your intention is a real "between" predicate, then the execution plan on the right is much better, because a single range scan with a start-top predicate delivers the matching row IDs only.
如果您的目的是要实现真正的“between”谓词,则右侧的执行计划会更好一些,因为带有启动谓词的单个范围扫描仅传递匹配的行id。
This example illustrates the effect of column group statistics on a qualifying OR predicate. Consider the following query on the EMPLOYEE table.
这个例子解释说明了列组统计信息对一个合格的OR谓词的影响。
Just as each progressive portion of an XPath is based on the set of nodes determined by the preceding path, the predicate of a set is based on the set that you apply it to.
就像XPath后面的部分依赖于前面路径所决定的节点集一样,集合的谓词也依赖于所应用的集合。
This example is legal if the database supports code set Shift_JIS code points that are used in the title predicate, but fails to execute correctly on other databases.
如果数据库支持题目谓词中使用的 Shift_JIS代码点,那么这个例子是合法的,但是在其他数据库上不能正确运行。
The predicate is specified using an XPath 2.0 expression which is part of the assertion specified on the type.
谓词通过XPath 2.0表达式指定,XPath 2.0表达式是类型指定的断言的一部分。
With the above statistics and predicate analysis, you have a clear idea on which statistics should be collected.
有了以上的统计数据和谓词分析,您应该清楚了解要收集哪些统计数据。
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