An index only scan is an index access that is not followed by a table access because the index itself contains all the requested data.
仅扫描索引是未包含表访问的索引访问，因为索引本身包含了所有被请求的数据。
The first method is often more effective, but because it requires indices and data to reside in different table Spaces, it may not be an option for existing databases.
第一个方法通常更为高效，但是因为它要求索引和数据驻留在不同的表空间，对于现有数据库不太适用。
Because of the number of table scans and table sorts in the TPC-H workload, prefetching data from disks into memory is important for optimal performance.
因为TPC - H工作负载中表扫描和表排序的数量较多，所以为获得最佳性能将数据从磁盘预取到内存是很重要的。
Due to the large amount of data in the audit log table, a single INSERT statement will usually fail because the data per transaction exceeds the log file size of the database system.
因为审核日志表格里有大量的数据，单独的insert语句通常会失败，这是因为每个事务的数据超过了数据库系统里的日志文件的容量。
Partition the table space as evenly as possible, because the degree of parallelism is influenced by skews in the data.
尽可能均匀地对表空间分区，因为数据不整齐会对并行度产生影响。
The code snippet in Listing 7 retrieves a database table, because the runtime data will be pushed to that table.
列表7中的代码用于获取数据库表，因为运行时数据将会装入到这个表。
Because new rows are inserted in the part of the table that contains rows with similar values, data remains clustered without the need to run the REORG utility.
由于新行是插在表中具有近似值的行附近的位置，因此数据仍然是聚合的，而不需要运行REORG实用程序。
Because they are not logged, the external table data files are excluded from all the replications.
由于不载入日志，外部表数据文件都不能进行复制。
Because customers use different as well as unexpected amounts of data, table space sizes can vary significantly, affecting database sizing and planning considerations.
由于客户使用的数据量各不相同而且大小不定，所以表空间变化很大，会影响数据大小调整和规划方面的考虑。
What about the entire periodic table? That exercise is trickier because you have to arrange the data into the familiar format based on group and period, which requires some fancy coding.
这个练习需要更多技巧，因为要按照分组和周期将数据排列成常见的格式，所以需要某些具有想像力的代码，不能简单地将各部分放在固定的位置。
Purge: in some recent history tables, every few days the entire table is dropped and recreated because data is now available in another table with a longer history.
清洗：在某些最近历史表中，每过一些天就删除整个表，并重新创建表，数据将放在有更长历史的另一个表中。
This is a very powerful part of RDA because you can even sample the contents of the table and make any necessary changes to the data where needed.
这是RDA中非常强大的一个部分，因为可以查看表的内容和做任何必要的修改。
Though this improves performance, it is not an optimal solution because the table is larger and all applications that manipulate or access the data must include logic that handles ucname.
尽管这样做改善了性能，但并不是理想的解决方案，因为表非常大，而且所有需要操纵或访问数据的应用程序必须包括处理 ucname 的逻辑。
Data table controls are more complex, because they contain multiple child controls, such as Columns.
数据表控件更加复杂，因为它们包含了多个子控件，例如Columns。
Because you just imported DB2 metadata about the target data warehouse table, this is a convenient point to work on the DB2 Connector stage.
因为刚刚导入了关于目标数据仓库表的DB 2元数据，可以在这里开始处理DB 2Connector阶段。
In most cases, ALTER SET DATA TYPE requires table reorganization (reorg) because it changes the physical row format.
大多数情况下，ALTERSETDATATYPE需要对表执行重组(reorg)，因为它修改了物理行格式。
In this example, the first thing the optimizer does is to evaluate the condition that state equals NEVADA, because that will rule out a large number of data rows in the table.
本例中，优化器所做的第一件事就是评估state等于NEVADA的这个条件，因为这将排除表中的大量数据行。
In this case, a table scan is very expensive, because the Informix engine has to access data randomly.
该例中，表扫描极其昂贵，因为Informix引擎必须随机地访问数据。
This variable is necessary because the weather.bylocation data table is a so-called community table, maintained by the community and not by Yahoo!
此变量是必要的，因为weather.bylocation数据表是所谓的社区表，由社区进行维护而不是 Yahoo!
Because the text "Best in show" is outside a table data element, the new rule doesn't apply, as shown in Figure 4.
因为文本“BestInShow”在表数据元素之外，所以不会应用这个新规则，见图4。
Result: the data from the back-end testtab table is shown because the passthrough Read level is set to FORCE.
结果：后端testtab表中的数据显示，因为将passthroughRead级别设置为FORCE。
Because a table is made up of rows, each of which contains a number of cells, we achieve this mapping between the data provider and the table by first defining the row class and the cell class.
因为表是由行组成的，并且每个行包含多个单元格，所以我们首先定义row类和cell类，以实现数据提供程序和表之间的映射。
The values of the inner data set's parameters are from the link table's SOURCE_ITEMID column because a work item can find its sub - work item's WI_ITEMID by retrieving the data from Links table.
内部数据参数的值来自于联系表格的source_itemid列，因为一个工作项可以通过从Links表格中获得数据，来找到其子工作项的WI_ITEMID。
Table functions are powerful because it can make any data source appear like a DB2 table, which can be then used in normal SQL queries, join operations, grouping, and so on.
表函数的功能很强大，因为它可以使任何数据源看起来类似于db2表，然后就可以用于常规的SQL查询、连接操作和分组等。
This data set must include the WI_ITEMID column in the output, because this table provides the key that you will use to retrieve the links from these work items.
该数据集合必须包含输出中的wi_itemid列，因为该表提供了您将会使用到的键，来获取来自这些工作项的联系。
It's sometimes known as an associative array because data is associated with a key value, or as a hash table.
它有时候称为关联数组(因为数据与一个键值相关联)，或者作为散列表。
This is because XML documents, like LOBs, can be too large to fit within a single row on a data page of the table.
这是因为，LOB这样的XML文档体积庞大，无法放到表数据页面的单个行中。
This is because Oracle uses a lot of virtual memory, particularly with respect to its System Global Area (SGA), which is used to cache table data, among other things.
这是因为Oracle使用大量的虚拟内存，特别是对于其系统全局区域（SGA），这个区域用于缓存表数据和其他东西。
This is because they may contain pointers to the internal data recording symbols and data types, which are part of the old symbol table data being discarded inside GDB.
这是因为他们可能包含指向内部数据（记录符号和数据类型）的指针（旧的被GDB 放弃的符号表的一部分）。
This is because they may contain pointers to the internal data recording symbols and data types, which are part of the old symbol table data being discarded inside GDB.
这是因为他们可能包含指向内部数据（记录符号和数据类型）的指针（旧的被GDB 放弃的符号表的一部分）。
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