公开(公告)号：US06345266B1

公开(公告)日：2002-02-05

申请号：US09398685

申请日：1999-09-20

Applicant: Sukanta Ganguly ,  Chin Ming Kuo ,  Cheng Yang

Inventor： Sukanta Ganguly ,  Chin Ming Kuo ,  Cheng Yang

IPC: G06F1730

CPC classification number: G06F17/30091 ,  Y10S707/99931 ,  Y10S707/99932 ,  Y10S707/99935

Abstract: The invention relates to a distributed directory service that is constructed based on a predicate, i.e., a query from a client. The predicate is formed by the query (request) issued by the client. The predicate is used as an index for retrieving data from a plurality of directory servers. Retrieving the data has the following steps. Each directory server is designated by a designation predicate giving a range of data values stored in the directory server. A client predicate indicates desired information. The client predicate is compared with the designation predicates to determine which directory servers may contain information requested by the client predicate. In the event that a particular designation predicate indicates that a portion of the desired information may be stored on a particular directory server, an inquiry is sent to the particular directory server for the desired information. The retrieved information is transferred to the client computer. The predicate is used to form an index by sorting the predicate into a normal form. Steps in sorting the predicate into the normal form include the following. Each symbol of the predicate is represented by a numerical representation, for example the ASCII value used to represent the symbol in ordinary text files. The logical connectors and the predicates are sorted in numerical order of the numerical representation to form the normal form of the predicate. The directory may be chosen to be a database.

Abstract translation: 本发明涉及一种基于谓词构建的分布式目录服务，即来自客户端的查询。 谓词由客户端发出的查询（请求）形成。 该谓词用作从多个目录服务器检索数据的索引。 检索数据具有以下步骤。 每个目录服务器由指定谓词指定，给出存储在目录服务器中的一系列数据值。 客户端谓词表示所需信息。 将客户端谓词与指定谓词进行比较，以确定哪些目录服务器可能包含客户端谓词请求的信息。 在特定指定谓词指示所需信息的一部分可以存储在特定目录服务器的情况下，向特定目录服务器发送查询以获得所需信息。 检索到的信息被传送到客户端计算机。 谓词用于通过将谓词排序为正常形式来形成索引。 将谓词排序为正常格式的步骤包括以下内容。 谓词的每个符号由数字表示法表示，例如用于表示普通文本文件中的符号的ASCII值。 逻辑连接器和谓词按数字表示的数字顺序进行排序，以形成谓词的正常形式。 该目录可以被选择为数据库。