The first example shows how to force the optimizer to use a nonclustered index to retrieve rows from a table , and the second example forces a table scan by using an index of 0 优化器提示的两种方式。第一个示例说明如何强制优化器使用非聚集索引检索表中的行,第二个示例使用索引0强制执行表扫描。
If the view can use an index internally , you can create an index specification that is stored in the db2 database system catalog on the federated server , and used by the query optimizer 如果视图可以在内部使用索引,那么可以创建一个索引规范,存储在联邦服务器上的db2数据库系统编目中,供查询优化器使用。
Just like a carpenter will use a manual screwdriver sometimes and other times an electric screwdriver , sometimes an agile modeler will use an index card and other times a complex software design tool 就象木匠有时使用手动螺丝刀,而有时使用电动螺丝刀,有时灵活建模者使用索引卡,有时使用复杂的软件设计工具。
Bulk operations on a ttreeview are often painfully slow , because every time a node is referenced using an index , the ttreeview has to walk through its linked list of nodes to get to the specified index 对一个树开视图控件进行大量操作经常速度很慢,因为每一次节点都需要通过一个索引进行引用,树形视图控件必须遍历它的节点链表以获到特定的索引,这个例子演示了一种解决这一问题的方法。
How to rapidly stream ttreeview contents - bulk operations on a ttreeview are often painfully slow , because every time a node is referenced using an index , the ttreeview has to walk through its linked list of nodes to get to the specified index 对一个树开视图控件进行大量操作经常速度很慢,因为每一次节点都需要通过一个索引进行引用,树形视图控件必须遍历它的节点链表以获到特定的索引,这个例子演示了一种解决这一问题的方法。