In this example, we'll see how the plan changes when the statistics are not updated properly.
本例中，我们将看到没有正确更新统计数据时计划是如何变化的。
There is an attribute RUNSTATS TIMESTAMP on the table or index node of the access plan graph that indicates the last time when the statistics were collected.
在访问计划图的表或索引节点上会有一个RUNSTATSTIMESTAMP属性，它表示收集统计数据的时间。
SP: When scientists talk about climate, what we’re talking about is the statistics of weather.
科学家们在谈论气候时，实际都是在谈论关于天气的统计数据。
On the command line, you need to specify the interval (in seconds) to use when reporting statistics.
在命令行上，您需要指定要在报告统计信息时使用的间隔(以秒为单位)。
When distribution statistics are generated for the column "TYPE," the optimizer knows the real frequency of each model.
而一旦生成了关于“TYPE”列的分布统计信息，优化器即可了解每种型号真正的出现频率。
Once the statistics are gathered for a nickname, they are not automatically modified when the remote statistics are updated on the data source for the corresponding remote table.
如果为一个昵称收集了统计信息，那么在数据源上对相应远程表的远程统计信息进行更新时，这些统计信息不会自动更新。
It allows you to define a data change threshold, and statistics are refreshed only when the data change threshold is reached.
它允许您定义一个数据变化阈值，统计也只有数据变化阈值到达时才会更新。
You can see that DB2 has to evaluate less rows to execute the query when distribution statistics are available.
您可以看到，有分布统计信息的情况下，DB 2执行查询时需要计算的行数更少。
Then when we look at the statistics, all we see are a lot of assets in the fund that performed well and the underperforming fund that was merged out of existence isn't there anymore.
于是当我们去查阅统计资料时,只能看到资产规模巨大且运作良好的基金,那些运作不佳的基金,随着合并与它的纪录一起消失了
When generating statistics, DB2 offers the possibility to create so-called distribution statistics in addition to the basic statistics.
DB2在生成统计信息时，不但能提供基本统计信息，还允许创建所谓的分布统计信息。
Before examining distribution statistics, let's have a look at the basic statistics that are always collected for a table when RUNSTATS is executed.
在研究分布统计信息之前，我们先来看看基本统计信息，只要执行RUNSTATS即可收集这些表的相关统计信息。
When there is any data modification to the user tables, the catalog statistics tables are not automatically modified.
当用户表中发生数据修改时，目录统计信息表不会自动被修改。
When the necessary statistics are collected and available, MAXFREQ shows the frequency of the most frequently appearing value on the column.
在必要的统计信息被收集并可用时，MAXFREQ在列上显示最常见显示值的频率。
The sample shows that distribution statistics are of limited use when used in conjunction with parameter markers.
这个示例表明，如果将分布统计信息与参数标记一起使用，分布统计信息的作用就会受到限制。
When the SAMPLE database is initially created, statistics are not collected on the tables.
SAMPLE在创建最初，还没有在表上收集统计信息。
You must also apply the same understanding when looking at your Domino statistics; many of which are cumulative in nature.
在查看Domino统计数字时，还必须应用同样的理解；许多数字在本质上是累加的。
Now that you've seen how to access and analyze the JVM statistics generated when running one of Geronimo's sample Web applications, you can start analyzing your own applications.
既然了解了如何访问和分析运行Geronimo的某个示例Web应用程序时生成的JVM统计信息，就可以开始分析自己的应用程序了。
This would be useful to find the statistics for a particular time when amepat is run for long period with workload getting changed frequently.
在amepat运行了较长时间、工作负载频繁发生变化的情况下，这可能有助于找到特定时间的统计数据。
When statistics are enabled, the broker Explorer creates a subscription point in the broker's queue manager automatically for you to gather the snapshot data.
当统计功能启动时，BrokerExplorer在代理队列管理器中为您动态创建一个订阅点来收集快照数据。
If the compilation environment or table statistics have changed when the explain statement is issued, the compiler may generate a different access plan.
如果编译环境或表统计信息在explain语句执行时已经发生改变，那么编译器可能会生成一个不同的访问计划。
Statistics for objects are updated in the system catalog tables only when explicitly requested. There are several ways to update some or all of the statistics.
只有当进行显式的请求时，对象的统计信息才会在系统目录表中被更新。
While the device-level data is automatically enabled, transaction data such as transaction rates or transaction times is usually available only when Statistics are enabled on the device.
设备级数据是自动启用的，而事务数据（如事务率或事务时间）只有在对设备启用了Statistics时才有效。
When the LIKE statistics clause is specified in RUNSTATS, additional column statistics are collected.
当在RUNSTATS中指定LIKEstatistics子句时，将收集附加的列统计信息。
The statistics Advisor will let you know when it's time to update those catalog statistics and generate the command to do so-all you have to do is click a button.
StatisticsAdvisor会指出什么时候应该更新编目统计数据并生成所需的命令；您只需单击一个按钮即可。
They worry that this revision of the statistics will lead a confused public to question all mortality data, as happened when the numbers for AIDS were revised downward in 2007.
他们担心统计数据的改动将会使困惑的民众对所有的死亡数据产生怀疑，这种情况在2007年将艾滋病人数量减少时就发生过。
First analyze the access plan that the optimizer chooses when no distribution statistics are available, which is only basic statistics for the table CARS, and that its indexes exist.
首先来分析一下，在没有分布统计信息，而只有cars表的基本统计信息及其索引的情况下，优化器选择的访问计划是怎样的。
When running the job in the designer, the links with relevant statistics info will turn green if no errors are found (see Figure 21).
当在设计器中运行该任务时，如果没有发现错误，则含有相关统计信息的链接将变成绿色(参见图21)。
Inconsistent statistics may be caused when users collect the partial statistics, for example collecting table and index statistics individually, at different points in time.
用户只收集一部分数据可能会造成不一致的统计数据，例如，在不同时间分别收集表和索引统计数据。
The filter factors calculated based on the available quantile statistics are not exact, but the estimate error is below 5%, even when only 20 values are collected.
根据已有的分位数统计信息计算出来的过滤因子不是很精确，但即使只收集20个值，其误差仍然低于5%。
The filter factors calculated based on the available quantile statistics are not exact, but the estimate error is below 5%, even when only 20 values are collected.
根据已有的分位数统计信息计算出来的过滤因子不是很精确，但即使只收集20个值，其误差仍然低于5%。
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