索引也是一种DB 2对象(一个单独的VSAM数据集),它由一组排好序的键组成,这些键是从相应表中的一个列或多个列抽取出来的。
An index is a DB2 object (a separate VSAM dataset) that is comprised of an ordered set of keys extracted from one or more columns of the corresponding table.
如果为索引表空间使用较大的缓冲池,并且尽可能地将不同 insert排序,以便键值是排好序的,而不是随机的,就可以帮助加快索引维护。
You can help speed up index maintenance by using a large buffer pool for the index tablespace, and, if possible, ordering the inserts so that the key values are ordered, not random.
如果一个索引是负值,意味着是从列表末尾向前倒序计数查找相对应的位置。
If an index has a negative value, it counts backward from the end of the list.
在用一个序数索引的那些全序集合的笛卡尔积的一个集合上的词典序自身是全序。
The lexicographical order on the Cartesian product of a set of totally ordered sets indexed by an ordinal, is itself a total order.
在用一个序数索引的那些全序集合的笛卡尔积的一个集合上的词典序自身是全序。
The lexicographical order on the Cartesian product of a set of totally ordered sets indexed by an ordinal, is itself a total order.
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