Structured-text cataloging method, structured-text searching method, and portable medium used in the methods

A text searching system, comprising:

• a text cataloging sub-system in which a plurality of texts are cataloged for use as text search objects in a text search operation;
• a text searching server that causes a text database to be searched in response to a text search request;
• a text searching client from which a text search request is issued to the text searching server;
• and
• a network connecting the text cataloging sub-system, the text searching server, and the text search client;
• wherein the text cataloging sub-system creates a structure index based on the cataloging of the plurality of texts, the structure index containing context identifiers of character-string data derived from the cataloged texts;
• wherein said structure index has a tree-like structure composed of a plurality of metanodes;
• wherein a context identifier that uniquely identifies one of said metanodes is assigned to each metanode of said structure index;
• wherein a group of structure elements having the same position of appearance and the same element type for a plurality of texts are represented by a single metanode;
• wherein the text search request issued by the text searching client includes a search condition that is translated into a condition specification by the test searching server, from which condition specification the test searching server causes the structure index to be searched for agreement between the context identifiers and the search condition;
• and
• wherein the text searching server transmits a text search result to the text searching client upon completion of the search of the structure index.

A text searching system, comprising:

• a text cataloging sub-system in which a plurality of texts are cataloged for use as text search objects in a text search operation;
• a text searching server that causes a text database to be searched in response to a text search request;
• a text searching client from which a text search request is issued to the text searching server;
• and
• a network connecting the text cataloging sub-system, the text searching server, and the test searching client;
• wherein the text cataloging sub-system stores and updates a character-string index from texts input to be cataloged;
• wherein the character-string index includes partial character strings extracted from the input texts, each partial character string having a predetermined character count, character-position information of said partial character strings, a text identifier for uniquely identifying the text in the text database, and a context identifier of a metanode representing character-string data including the partial character strings in a structure index;
• and
• wherein the text cataloging sub-system updates the stored character-string index by generating structured-character-position information that includes the character-position information, the text identifier, and the context identifier, and by cataloging an associative relation between each of the partial character strings and the structured-character-position information in the stored character-string index.