Automatic table statistics collection policy.
自动表统计信息收集策略。
So for the table statistics, the CARD will show as 1,100,000.
因此对于表统计数据,CARD将显示为1,100,000。
Example 7: Collect catalog statistics on 3 specific indexes only (no table statistics).
示例7:只收集3个指定索引上的目录统计信息(不含表统计信息)。
Since the fragmented statistics are more granular than table statistics, they do take up more space as well.
因为片段统计比表统计更加细粒度,因此会占用更多的空间。
For example, refreshing of statistics can happen at fragment level, and fragment statistics can be added to, or removed from, table statistics.
例如,可以在片段级别上刷新统计数据,可以向表统计添加或从中移除片段统计。
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。
In this example, 10 percent of table data pages are used for the collection of table statistics, while for index statistics all of the index pages will be used.
本例中,10%的表数据页用于表统计信息的收集,而对于索引统计信息,将使用所有的索引页。
The automatic table statistics collection policy is used to control the behavior of automatic table statistics collection. The following elements are configurable.
自动表统计信息收集策略用于控制自动表统计信息收集的行为。
If your table statistics are up to date, you can quickly and inexpensively check the cardinality of the columns in your existing table by issuing the following statement.
如果表的统计信息是最新的,那么就可以通过如下语句快速检查现有表内列的基数。
Db2pd provides more than 20 options to display information about database transactions, table Spaces, table statistics, dynamic SQL, database configurations, and many other database details.
db 2 pd提供了20多个选项显示关于数据库事务、表空间、表统计信息、动态sql、数据库配置和其他很多数据库细节的信息。
Db2pd provides more than 20 options to display information about database transactions, table Spaces, table statistics, dynamic SQL, database configurations, and many other database details.
db 2 pd提供了20多个选项显示关于数据库事务、表空间、表统计信息、动态sql、数据库配置和其他很多数据库细节的信息。
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