索引

In a nonunique regular index, Oracle stores duplicate keys with the rowid

对于非唯一索引Oracle 会在每个重复的索引键之后添加 rowid 以便区分。

Not-deferrable unique constraints and primary keys also use a nonunique index if the nonunique index is placed on the key columns before the constraint is enforced.

如果在创建不可延迟的唯一约束或主键约束时，键列上已经创建了非唯一索引，上述约束将使用此非唯一索引。

IND_COL as the column is nullable as we may miss some rows.

IND_COL 上的索引，因为可空列的索引会使我们丢掉一些记录。

In this type of index, the partitioning is not on the left prefix of the index columns.

此类索引的特点是，不对索引键的左前缀进行分区。

Scopus is the largest abstract and indexing database in the world at present. The appearance of it has brought new color to development of indexing tools abroad.

Scopus数据库是目前世界上规模最大的文摘和索引数据库，它的出现给国外索引工具的发展增添了新的色彩。

The question's semantic comprehension model combines many natural language processing techniques, including Segmentation and Part-Of-Speech Tagging, the confirmation of the question type, the extarction of keywords and extending, the confirmation of the knowledge unit, Through these works, the intention of the user is holded, which greatly helped the last work of this system. The FAQ-based question similarity match model is implemented by sematic sentence similarity computation, which is improved by our system, this model can answer frequently-asked question fastly and concisely.The document warehouse-base automatic answer fetching model fistly deal with the document warehouse beforehand and construct inversed index, then use high efficient information retrieval model to search in the base and return some relevant documents, lastly, we use answer extraction technique to get the answer from these relevant documents and present it to users.

问句理解分析模块采用分词和词性标注、关键词提取及扩展、问句类型类别确定等自然语言理解技术，实现对用户提问意图的准确理解；FAQ 库问句匹配模块主要采用本系统改进的句子相似度计算方法来实现用户问句的解答，该模块主要用于实现用户常问问题的快速、准确解答；学科文档库答案自动获取模块在对学科文档库建立倒排索引的基础上，采用高效的信息检索模型对索引库进行检索，返回与用户查询表达式相似度较高的文档作为候选文档，针对从文档中直接获取答案难度较大这一问题，本系统采用答案抽取技术来实现问题的最终回答。

The calligraphic character is firstly skeletonized with morphology fused index table skeletonization method, in which the character is thinned by an index table and then thinned with mathematic morphology method.

首先用融合数学形态学的索引表骨架提取方法获取骨架，即先使用索引表对书法字进行初步细化，再用数学形态学的方法细化得到骨架。

Because of the depth and breadth of information being indexed, there is usually a delay, sometimes up to several weeks, between the time a site has been"spidered"and when it appears in a search index.

由于已编索引的信息的深度与广度，所以通常在&蜘蛛爬行过&站点的时间与出现在搜索索引中的时间之间有一个延迟，有时多达几周。

Steg B(superscript +)-Tree, which uses steganographic technologies to overcome above mentioned weakness is presented by hiding the existence of data so that an adversary could get no information about whether the protected data ever exists without correct object name and access key.

介绍一种新的着重于隐藏数据的存在性的加密手段－隐文加密（Steganography，隐写术）来对重要文件的存储进行加密，该方法采用隐文B树Steg B(上标+ Tree建立UNIX系统的文件索引，并通过隐藏表将隐文B树索引隐蔽起来，使攻击者无法知道重要信息的存在，从而使要保护的信息更安全。

Local partitioned indexes support more availability when there are partition or subpartition maintenance operations on the table.

当对表的分区及子分区进行维护操作时，本地分区索引与全局索引相比具备更高的可用性。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。