JP2004046906A - Information retrieval system, information retrieval method, and recording medium recording program for information retrieval - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To retrieve information by using the same retrieving method against pieces of data of a plurality of external information sources. <P>SOLUTION: In the integration type information retrieval system, an external information source searching means 78 reads pieces of data from the external information sources when creating indexes, a data converting means 76 determines whether or not data conversion is necessary with respect to an attribute of an object to be indexed in the data, and if it is necessary, an attribute value is converted. An equation calculating means 75 and an index creating means 77 creates an index and registers it in an index storing part 34 and an index value storing part 35 with respect to the value processed by the data converting means 76. A retrieval equation evaluating means of the information retrieval system carries out specified conditional retrieval of inquiry by index retrieval using the registered indexes. <P>COPYRIGHT: (C)2004,JPO

Description

The present invention relates to an information search system, an information search method, and a recording medium on which an information search program is recorded, and more particularly to an information search system, an information search method, and an information search program product that can quickly extract target information from a large-scale information source. Further, the present invention relates to a medium (especially a recording medium) carrying the same.

Conventionally, information retrieval means is used to retrieve data stored therein in an information source such as a database management system, a data warehouse, and a data mart, and to return a requested value, data, or a set thereof. I have.

A query, which is a search request for a certain information source, generally includes a search condition expression and an output expression for specifying what to return as a search result. SQL (Structured Query Language) language is generally used to query the database, which is one of the information sources. In SQL, for example, a query including a search condition expression and an output expression is described by the following expression. I do.
SELECT <output expression>
FROM <search target list>
WHERE <search condition expression>
FIG. 1A is a block diagram showing a configuration of a conventional information search system that interprets a query and returns a search result.

Referring to FIG. 1A, a conventional system includes an input device 1 such as a keyboard, a data processing device 2 operated by program control, a storage device 3 for storing information, and an output device such as a display device or a printing device. And 4 inclusive.

The storage device 3 includes an index storage unit 31 and an actual data storage unit 30.

(4) The actual data storage unit 30 holds information in a data structure determined by the system.

The index storage unit 31 holds an index, which is a pair of an arbitrary attribute value or a combination thereof extracted from actual data and an ID for uniquely identifying the actual data. This ID is hereinafter referred to as a data ID (or simply "ID" if no misunderstanding occurs). The data ID secures uniqueness in the system by a unique value or a combination of a plurality of values. In general, an index is managed by a structure such as a B-tree or a hash.

The data processing device 2 includes a search unit 21 and an index generation unit 22.

The search unit 21 includes a search expression evaluation unit 211, an output expression evaluation unit 212, an index search unit 213, and an actual data search unit 214.

The search expression evaluation unit 211 analyzes the query character string provided from the input device 1 and acquires a set of data IDs satisfying the condition using the index search unit 213 or the actual data search unit 214. If the attribute in which the index is generated is described in the conditional expression of the query, the search is performed using the index search means 213; otherwise, the search is performed using the real data search means 214.

The output expression evaluation unit 212 creates a search result in the format specified by the output expression for the set of data IDs that are the search results of the search expression evaluation unit 211, and outputs the result to the output device 4. In creating the search result, the actual data search means 214 acquires the attribute value specified in the output expression.

(4) The index search means 213 searches the index storage unit 31, acquires the ID of the actual data having the attribute value satisfying the condition, and returns it.

(4) The actual data search unit 214 searches the actual data storage unit 30 to find an ID of actual data that satisfies the condition. Further, the real data corresponding to the given data ID or the designated attribute value is obtained from the real data storage unit 30.

The index generation means 22 reads the real data from the real data storage unit 30 prior to the search, generates an index for a specified attribute or a combination thereof, and stores it in the index storage unit 31.

In recent years, applications such as OLAP (OnLine Analytical Processing) and data mining that search and analyze large amounts of data using such information retrieval systems are increasing. In this type of application, data is classified by executing multiple queries based on gradually changing conditions, calculations are performed on the attributes of the data, and the characteristics of the entire data are analyzed using the obtained values. And other processing.

In particular, in the field where various mining methods involving various calculations have been proposed, such as data mining, and they are being continuously improved, it is necessary to support the high-speed calculation of the calculation methods required for each method. is there. Further, it is desirable that a high-speed data retrieval method (index) corresponding to the characteristics of the data handled therein be supported.

ア プ リ ケ ー シ ョ ン In applications that handle multimedia data such as images and sounds, it is desirable that the index method unique to each medium and the multidimensional index method for multidimensional data be flexibly captured and used.

Furthermore, with recent advances in computer technology, the amount of data that can be managed by various information sources has dramatically increased, and some have a size of several gigabytes to several terabytes. Therefore, in an application that handles such a large amount of data, it is desirable to maximize the index in the search processing and reduce the number of times of accessing the actual data as much as possible.

検 索 When searching for multiple information sources, a higher-level application that issues queries to the information search systems corresponding to each information source and integrates the results is used. This higher-level application is hereinafter referred to as an integrated information search system.

As shown in FIG. 1B, this type of conventional integrated information search system 5 includes a search mediation unit 51. The search mediation unit 51 sends the query input from the input device 1 to the information search systems 61 to 63 (the number of information search systems is arbitrary). At this time, since the data management format and the inquiry method of each information search system are generally different, the search mediation means 51 has a function of converting the query into a format that can be interpreted and executed by each information search system. .

検 索 The search results of the information search systems 61 to 63 are returned to the search mediation means 51. The search mediation unit 51 integrates the result, converts the data format if necessary, and outputs the result to the output device 4.

The first problem of the conventional information retrieval system is that it is not possible to flexibly apply various indexing methods according to data characteristics and application characteristics. The reason is that one information search system provides a general-purpose index function and a real data management function at the same time, and cannot change them freely.

The second problem is that even when indexes are generated for all attributes included in the output expression of the query, all actual data satisfying the search condition is loaded into the memory in order to create a query result. That's what it means. As a result, when the search results are large, a large processing cost is required to generate the query output. The reason is that the conventional information retrieval system does not have means for using an index to generate an inquiry output.

(3) The third problem is that there is no means for retrieving actual data at high speed based on a value obtained by processing an attribute value. The reason is that the conventional index manages only attribute values and combinations thereof, and has no means for generating an index for a value obtained by processing the attribute value.

The fourth problem is that the integrated information retrieval system is difficult to implement. The reason is that a given query is converted into a format according to the data model, data structure, and search interface of any information retrieval system, and the process of integrating and outputting the returned data is standardized and automated. Because it is difficult.

An object of the present invention is to provide an integrated information search system with higher integration of data from a plurality of external information sources whose data structure has a difference of a degree that can be automatically converted by a program. In particular, an object of the present invention is to provide an information search system that can execute a search process using the same search formula.

Another object of the present invention is to provide an information retrieval system that can flexibly apply various indexing methods that are optimal for characteristics of data and applications.

It is still another object of the present invention to provide an information retrieval system that does not require loading of all actual data satisfying a retrieval condition into a memory, and in particular, information retrieval that can use an index to generate a query output It is to provide a system.

Still another object of the present invention is to make it possible to more efficiently search information including a large number of indexes corresponding to various attributes, in particular, to generate an index for a value obtained by processing an attribute value, and generate the index. It is to provide an information retrieval system that can be used.

In a first aspect of the present invention, an information search system includes a data conversion unit that converts attribute values in a plurality of information sources into a predetermined unified format, and an index for the value converted by the data conversion unit. Index generation means for generating, index search means for performing an index search using the index generated by the index generation means, search expression evaluation means for performing a conditional search to specify a query using the index search means, It is characterized by having.

In a second aspect of the present invention, an information search system includes: an expression calculating unit that processes an attribute value by a specified method; an index generating unit that generates an index for a value generated by the expression calculating unit; Index search means for performing an index search using the index generated by the index generation means, and search expression evaluation means for performing a conditional search specified by a query using the index search means, I do.

In a third aspect of the present invention, an information retrieval system comprises: a data conversion unit for converting attribute values in a plurality of information sources into a predetermined unified format; and a method for specifying a value converted by the data conversion unit. Formula calculation means for processing, index generation means for generating an index for the value processed by the formula calculation means, index search means for performing an index search using the index generated by the index generation means, A search expression evaluation unit for performing a condition search specified by a query using the index search unit.

In a fourth aspect of the present invention, the information retrieval system comprises: an index value storage unit that manages an ID for uniquely identifying data in an information source and values of all attributes for which an index is generated; An index value search means for searching from an index value storage means, and an output expression evaluation means for generating a query result according to a query output expression by the index value search means.

In a fifth aspect of the present invention, an information retrieval system comprises: a formula calculating means for processing an attribute value by a designated method; and a set of a value generated by the formula calculating means and an ID of data having an original attribute. Index value generating means for generating index value information comprising: an index value searching means for obtaining a value processed by the formula calculating means from the index value information generated by the index generating means; and the index value searching means. Output expression evaluation means for generating a query result according to the output expression of the query.

In a sixth aspect of the present invention, an information search system includes: a data conversion unit configured to convert attribute values in a plurality of information sources into a predetermined unified format; and a data conversion unit configured to convert a value converted by the data conversion unit and an original attribute. Index generating means for generating index value information comprising a set of data IDs having the index value searching means for obtaining a value converted by the data converting means from the index value information generated by the index generating means; and Output expression evaluating means for generating a query result in accordance with the output expression of the query using the value search means.

In a seventh aspect of the present invention, an information retrieval system comprises: a data conversion unit for converting attribute values in a plurality of information sources into a predetermined unified format; and a method for specifying a value converted by the data conversion unit. Formula calculating means for processing, index generating means for generating index value information comprising a pair of a value processed by the formula calculating means and an ID of data having an original attribute, and an index generated by the index generating means An index value search means for obtaining a value converted and processed by the data conversion means and the expression calculation means from the value information; and an output expression evaluation for using the index value search means to generate a query result according to a query output expression. Means.

In the eighth aspect of the present invention, the present invention provides an information search method corresponding to each of the first to seventh viewpoints. Each feature is as described in each section of the claim, and to avoid long culture, each section is referred to here with reference to each section, and redundant description is omitted.

In a ninth aspect of the present invention, the present invention provides a computer-readable program product for implementing an information retrieval method according to the claims. Each feature is as described in the claims, and each description is incorporated in this section with reference to each section.

Note that the program product is typically embodied as a program product recorded on a recording medium, but the disclosure of the present invention is not limited thereto, and the program may be implemented in any form of storage device in general (such as a memory device). ) And a carrier carrier as a medium.

(1) The first effect is that an inquiry process can be executed at a high speed for a plurality of information sources. The reason is that data from a plurality of external information sources whose data structures differ in the degree (or range) that can be automatically converted by a program can be converted by data conversion means to generate an index in a unified format. This is because there is a means for executing an inquiry process using this index.

Further, the second effect that the index method optimal for each characteristic of the data and the application can be flexibly applied independently of the information source (the characteristic of the data and the application) holding the actual data is also exerted. You. This is because index information suitable for searching by the index searching means and its own index searching means is provided independently of the information source.

{Circle around (3)} When indexes have been generated for all the attributes described in the query, the third effect that the load processing of the actual data becomes unnecessary and the query processing time can be shortened is also exerted. The reason is that, for one piece of data, each value of all attribute values for which an index is generated and each data ID are integrated and managed, and an inquiry process is performed using the index value.

{Circle around (4)} Further, the fourth effect that the query result can be generated without calculating the expression including the attribute is also exerted, and as a result, the response speed of the query can be reduced. The reason is that an index for each value itself of the expression for processing the attribute value is generated, and a means for acquiring and using the value of the expression by maintaining the correspondence between the expression and the index is provided. .

The first information retrieval system form of the present invention has a query processing function and an index management function independently of an information source that manages actual data, and an index is already created in a retrieval condition expression and an output expression of a query. When an attribute is specified, a query result is generated using only the index value. More specifically, search expression evaluation means (711 in FIG. 2), output expression evaluation means (712 in FIG. 2), index search means (213 in FIG. 2) and index value acquisition means (713 in FIG. 2) If an index is generated for all attributes included in the query, the index value is managed in the index value storage unit (32 in FIG. 2) without accessing the external information source (91 in FIG. 2). It operates to generate a query result using the index value that exists.

{Circle around (2)} The second information retrieval system form of the present invention manages not only the attribute in the query but also an index for an expression (processing expression) including the attribute, and generates a query result using the value. More specifically, it is provided with an expression calculating means (75 in FIG. 5) for calculating the value of the attribute and an index information storage unit (33 in FIG. 5), and whether the expression including the index is included in the query. The index information storage unit is checked for information as to whether or not it is included, and if it is included, an operation is performed to generate a query result using the index value managed in the index value storage unit (32 in FIG. 5).

In the third information search system according to the present invention, the data formats of a plurality of external information sources are unified and managed by the same index. More specifically, a data conversion means (76 in FIG. 8) is provided, and for the same type of data in different data formats in a plurality of external information sources, the data format is unified into one and the unified values are obtained. By generating an index for the information, an operation is performed to execute one query for a plurality of external information sources.

Next, each embodiment of the present invention will be described in more detail with reference to the drawings.

[Embodiment 1]
Referring to FIG. 2, a first embodiment of the present invention includes an input device 1 such as a keyboard, a data processing device 7 operated by program control, a storage device 8 for storing information, a display device and a printing device. And an output device 4.

The storage device 8 includes an index storage unit 31 and an index value storage unit 32. The index storage unit 31 holds an index that is a pair of an arbitrary attribute value or a combination thereof extracted from real data and a data ID that can uniquely identify the real data.

The index value storage unit 32 holds the value of an attribute for which an index is generated in the index storage unit 31 (hereinafter, this is referred to as an index value) and an ID uniquely added to actual data. When different indexes are generated for a plurality of attributes, all index values corresponding to the respective attributes are held in association with the IDs.

The data processing device 7 includes a search unit 71, an external information source search unit 73, and an index generation unit 74. The search unit 71 includes a search expression evaluation unit 711, an output expression evaluation unit 712, an index search unit 213, and an index value acquisition unit 713.

The search expression evaluation means 711 analyzes the query character string provided from the input device 1 and searches the index search means 213 or the external information source search means 73 for data satisfying the condition.

(4) The output expression evaluating means 712 generates an inquiry output by the index acquiring means 713 or the external information source searching means 73 for the set of data IDs which are the search results of the search expression evaluating means 711, and sends it to the output device 4.

The index search means 213 searches the index storage unit 31 and acquires the ID of data having an attribute value satisfying the conditional expression.

(4) The index value acquisition unit 713 extracts the specified attribute value of the data corresponding to the given ID (set) from the index value storage unit 32 and returns it.

The external information source 91 is an information source such as a database, and provides the data search means by itself.

(4) The external information source search means 73 transfers the processing of the given inquiry to the external information source 91 that holds the actual data. Further, the designated attribute value of the data corresponding to the given data ID is obtained from the external information source.

The index generation unit 74 reads the actual data using the external information source search unit 73, generates an index for the specified attribute or a combination thereof, and stores it in the index storage unit 31 prior to the search. At the same time, the index value is registered in the index value storage unit 32. When an index is generated for a certain data for the first time, a data ID and index value pair is registered in the index value storage unit 32, and thereafter, an index value is added to the first generated data ID and index value pair. I will do it.

Next, the overall operation of the present embodiment will be described in detail with reference to the flowcharts of FIGS.

First, the index generation processing will be described with reference to FIGS. 2 and 3B.

(4) First, predetermined data is read from the external information source 91 by the external information source searching means 73 (320 in FIG. 3B). Next, an index is generated by the index generating means 74 (321) and registered in the index storage unit 31 and the index value storage unit 32 (322). The reading of the “predetermined data” itself can be performed in a known manner based on the designation of each search field, the target keyword, etc., which is suitable for the external information source associated with each desired attribute.

Next, the search processing will be described with reference to FIGS. 2 and 3A.

First, the query input from the input device 1 is analyzed by the search expression evaluation means 711 (301 in FIG. 3A). Then, the index storage unit 31 is searched to determine whether indexes have been generated in advance for all attributes included in the search condition expression of the query (302). If indexes have been generated for all attributes, the index search means 213 searches the index storage unit 31 to obtain an index value and evaluates a search condition expression (303). If an attribute for which an index has not been generated is included, the processing of the entire query is transferred to the external information source 91 by the external information source searching means 73 (304), and the obtained result is output from the output device 4 as it is (310). ).

(4) If indexes have been generated for all the attributes in the search expression, next, a process of outputting the search results is performed. First, the output expression evaluation means 712 determines whether the output expression being queried includes an attribute (305). If not included, the output expression evaluation means 712 evaluates the output expression (306) and outputs the result (310).

(4) If the output formula includes attributes, it is determined whether or not indexes have been generated for all of the attributes (307). When indexes have been generated for all the attributes, the index value obtaining unit 713 searches the index value storage unit 32 and extracts the attribute value specified by the output expression (308). If an attribute for which an index has not been generated is included, the attribute value is extracted from the external information source 91 by the external information source search means 73 (309). At this time, the data extracted from the external information source 91 targets only the data extracted as a result of the index search (303) for the search condition expression. Finally, a processing result is generated and output according to the output equation (310).

Next, the effects of the present embodiment will be described.

In the present embodiment, since the index storage unit 31 and the index search unit 213 are configured to be implemented separately from the actual data of the external information source 91, the index storage unit 31 and the index search unit 213 are independent of the information source that manages the actual data. Various indexing techniques can be applied.

Further, in the present embodiment, when the search result is generated along the output expression of the query, when the indexes are generated for all the attributes included in the output expression, the search result is stored in the index value storage unit 32. Since the configuration is such that the value is used, it is not necessary to load the actual data from the external information source 91 to generate the output, and the time required for loading can be saved.

[Example 1]
Next, the operation of the first embodiment will be described using a specific example.

As shown in FIG. 4, various attributes (here, in the present embodiment) are stored in the index storage unit 403 by the index generation means 74 in advance for the employee table 402 in which employee information (actual data) in the external information source 401 is recorded. , Name, date of birth (and / or age), position, etc.). That is, it is assumed that a name index 404 for the attribute “name”, a birth date index 405 for the attribute “birth date”, a post index 406 for the attribute “post”, and a belonging index 407 for the attribute “affiliation” have been generated.

The index value storage unit 408 stores an index value table 409 for managing the correspondence between all of these index data IDs and values. One row in the index value table 409 holds the ID of one data and the values of all the attributes of the data for which an index is generated. The index value held in the index value table 409 may be either a pointer to an index value in each index stored in the index storage unit 403, or a copied value itself. As long as the memory area occupied by the copied index value does not overwhelm the machine environment, the performance is better when the copied value is held.

Here, it is assumed that the query “Search for the name of the section manager of the general affairs department among employees” is input. This is expressed in SQL as Query 1. Here, E represents the employee table 402.
SELECT E. name
FROM E
WHERE E. Affiliation = 'General Affairs' AND E. Title = 'Manager'; [Query 1]

First, the search expression evaluation means 711 searches the index storage unit 403, and confirms that an index has been generated for the attributes “affiliation” and “post” in the search condition expression (WHERE of query 1 and below). Since there is no other attribute in which no index is generated in the conditional expression, the index search unit 213 acquires an index value from the corresponding index in the index storage unit 403, and performs a condition determination. As a result, a data ID set satisfying the search condition is obtained.

Next, the output expression evaluation means 712 evaluates the output expression “E. name” in order to generate a search result. The attribute "name" contained therein has an index generated, and does not include any other attribute for which no index has been generated. Therefore, the index value obtaining unit 713 reads the result from the index value storage unit 408. Extract the value of "name" corresponding to each element of the ID set of. Then, they are returned to the output device 4.

In the case of the following query 2, the output expression differs from that of query 1, and the output expression does not include any attributes. For this reason, the evaluation of the search expression performs the same processing as that of the query 1, but the evaluation of the output expression does not access the external information source 401 based on the evaluation result of the search expression, but the own system (output expression evaluation means). The evaluation can be completed within 712) (306 in FIG. 3A).
SELECT COUNT (*) AS N
FROM E
WHERE E. Affiliation = 'General Affairs' AND E. Title = 'Manager'; [Query 2]

In the above processing, since the evaluation can be completed in the own system without accessing the external information source 401 to evaluate the entire query, the load time of the actual data from the external information source 401 is omitted. be able to.

On the other hand, in the case of Query 3 below, since the search condition expression includes the attribute “job class” for which no index has been generated, the search evaluation unit 711 processes the external information source 401 using the external information source search unit 73. Is transferred (304 in FIG. 3A). Then, the search result returned from the external information source 401 is returned to the output device 4 (310).
SELECT E. name
FROM E
WHERE E. Position = 'Manager' AND E. Position <>'A7'; [Query 3]

Here, consider another indexing method, for example, a case where a similar image search index is introduced for employee face photograph data (attribute “face”). In this case, the similar image search index generation unit is incorporated as the index generation unit 74, the similar image search index search unit is incorporated into the index search unit 213 and the index value acquisition unit 713, and the index storage unit 403 and the index value storage unit 408 are used. , The value (information) of the similar image search index may be stored, and the external information source 401 is not affected.

[Embodiment 2]
Next, a second embodiment of the present invention will be described in detail with reference to the drawings.

Referring to FIG. 5, in the second embodiment of the present invention, the configuration of the storage device 13 is different from the configuration of the storage device 8 in the first embodiment shown in FIG. In that it has Further, the configuration of the data processing device 10 is different from the configuration of the storage device 7 in the first embodiment shown in FIG.

The index information storage unit 33 manages the correspondence between the attribute registered as an index and the index set in the index storage unit 31. When an index is generated for a value obtained by processing an attribute, the correspondence between the processing formula and the index is managed.

When generating an index for a value obtained by processing an attribute, the formula calculation means 75 performs processing for processing (calculating) the attribute value to generate an index value. It is assumed that the attribute value processing method is specified in advance by the user.

(5) The overall operation of the present embodiment will be described in detail with reference to the flowcharts of FIGS.

First, the index generation processing will be described with reference to FIGS. First, the generated index information is registered in the index information storage unit 33 (620 in FIG. 7). The index information includes, in addition to the table name and the attribute name of the index generation target data, information on the processing formula when a processed value of the attribute is registered in the index. Next, data is read from the external information source 91 by the external information source search means 73 (320). If it is specified that the value obtained by processing (calculating) the attribute is to be indexed (621), the index value is calculated by the formula calculating means 74 (622). If not specified, the formula calculation means 74 does nothing. Finally, the index generation means 74 generates an index by a designated method (321), and registers it in the index storage unit 31 and the index value storage unit 32 (322).

Next, search processing will be described.

First, the search expression evaluation means 711 analyzes the query input from the input device 1 (301 in FIG. 6), searches the index information storage unit 33, and includes, in the search condition expression, an expression or attribute for which an index has not been generated. Investigate whether it is possible (601). If an expression or attribute for which an index has not been generated is included (YES), the external information source searching means 73 delegates the search processing to the external information source 91 (304).

(4) If an index is generated for an expression in the search condition expression, the index storage unit 31 is searched to obtain an index value (603). Next, for all attributes for which an index value has not been obtained, the index search means 213 searches the index storage unit 31 to obtain an index value, evaluates a search condition expression, and obtains a data ID satisfying the condition ( 303).

(4) Next, a process of outputting a search result is performed. First, the output expression evaluation means 712 determines whether the output expression being queried includes an attribute (305). If not included, the output expression is evaluated by the output expression evaluation means 712 to generate a result (306).

If the output expression includes an attribute, the index information storage unit 33 is searched to determine whether indexes have been generated for all attributes or expressions (604). If an index or an attribute for which an index has not been generated is included, the external information source searching means 73 extracts an attribute value from the external information source 91 only for a data set that satisfies the search condition (309), and outputs it. Generating an Expression (310) If an index has been generated, the index value obtaining unit 713 searches the index value storage unit 32 and extracts the value of the expression specified by the output expression. If an index has been generated for the expression (605), the index value of the expression is obtained (606), and the remaining attribute values are extracted (308). Finally, a processing result is generated and output according to the output equation (310).

Next, the effects of the present embodiment will be described.

In the present embodiment, since the index information storage unit 33 is configured to manage the index generated in the expression including the attribute, the condition determination and the value determination are performed without calculating the value of the expression including the attribute. Retrieval and search result generation can be performed.

[Example 2]
Next, the operation of the present embodiment will be described using a specific example 2.

年 齢 As shown in FIG. 8, it is assumed that the index storage unit 702 has generated an age index 705 in which the value of the expression “age (date of birth)” is calculated in advance by the expression calculating unit 75. Here, "age ()" is a function for calculating age. At this time, the index information storage unit 701 simultaneously manages not only the index information for the attribute but also the index information corresponding to this expression. In this embodiment, the index information table 704 stores information on the age index.

Here, it is assumed that the query “Search for the names of section managers over 50 years old among employees” is input. This is expressed in SQL as Query 4.
SELECT E. name
FROM E
WHERE E. Position = 'Manager' AND age (E. Date of birth)>50; [Query 4]

At this time, the search expression evaluation means 711 searches the index information table 704 of the index information storage unit 701, and knows that an index has been generated for the expression "age (E. Birth date)" (602). As a result, the index search means 213 searches the index corresponding to “age (E. birth date)” (603), and evaluates the search condition expression. At this time, since the value of “age (E. date of birth)” is obtained from the age index 705, there is no need to calculate using the value of the attribute “date of birth”.

[Embodiment 3]
Next, a third embodiment of the present invention will be described in detail with reference to the drawings.

Referring to FIG. 9, according to a third embodiment of the present invention, the configuration of the data processing device 12 is different from the configuration of the data processing device 10 in the second embodiment shown in FIG. It differs in having 76. Another difference is that the search target of the external information source search means 78 is not a single target but a plurality of information sources (91, 92, 93).

The data conversion means 76 acquires the attribute values for index creation from a plurality of external information sources, and unifies the data format. It is assumed that the conversion means is provided in advance for each information source in order to unify the data format.

In the index storage unit 34, the index storage unit 31 in the first embodiment and the second embodiment holds only the ID of data corresponding to each attribute value because it targets a single information source. In order to manage an index for data in a plurality of information sources, an information source ID for uniquely specifying an external information source and a data ID for specifying data among the information sources are held.

The index value storage unit 35 is also different from the index value storage unit 32 in the first and second embodiments in that an information source ID for uniquely specifying an external information source and data in the information source are stored. Holds a set of attribute values resulting from conversion to unify the data ID and format for specifying

The index generation unit 77 generates an index using a pair of an attribute value and a data ID in the index generation unit 74 according to the first and second embodiments. Generate an index with a set of source IDs.

(4) The external information source searching means 78 sets a plurality of information sources as search targets, and accesses a specified information source among them.

The index search means 717 uses the index of the index storage unit 34 to obtain a data set satisfying the search condition. At this time, not only the data ID but also the information source ID is obtained at the same time, and the pair is returned as a result. I do.

The output expression evaluating means 716 receives the set of pairs of the information source ID and the data ID from the index searching means 717, and obtains the specified attribute value corresponding thereto by the index value obtaining means 718 or the external information source searching means 78. Then, a search result in a specified format is generated from the obtained value and output to the output device 4.

全体 The overall operation of the present embodiment will be described in detail with reference to the flowcharts of FIGS.

First, in order to generate an index, data is read from the external information source by the external information source search means 78 (620 in FIG. 10). Next, the data conversion means 76 determines whether data conversion is necessary for the attribute for which an index is to be generated in the read data (901). If data conversion is necessary, the attribute value is converted by a conversion means registered in advance (902). It is assumed that information on whether or not data conversion is necessary for index generation for an attribute of a certain information source and conversion means are defined and provided by the user for each information source and each attribute to be indexed. If data conversion is not required, the data conversion means 76 does nothing.

Next, for the value processed by the data conversion means 76, an index is generated by the formula calculation means 75 and the index generation means 77 (621, 622, 321) and registered in the index storage part 34 and the index value storage part 35. (322).

検 索 The search method using the generated index is the same as the method in the second embodiment. However, at this time, since the ID of the external information source and the data ID are included from the index storage unit 34, when searching for the external information source (309 in FIG. 6), the external information source searching means 78 uses the two IDs. Extract data based on

Next, the effects of the present embodiment will be described.

The present embodiment is configured so that data of a plurality of external information sources having a difference in a data structure that can be automatically converted by a program in a data structure can be converted by a data conversion unit 76 and index generation can be performed in a unified format. Therefore, a search over a plurality of information sources can be executed at high speed using the same search formula.

[Example 3]
Next, the operation of this embodiment will be described using a specific example 3.

{Suppose that there is an external information source 401 and an external information source 1003 that both manage employee information as shown in FIG. Although the contents of employee information managed by the external information source 401 and the external information source 1003 are almost the same, the management method of the date of birth data is based on the year in the employee table 402 of the external information source 401, whereas the external information source It is assumed that the data format is slightly different so that the employee table 1004 of 1003 is managed in the Japanese calendar.

(4) When data is extracted from the external information source 401 and the external information source 1003 and an index is generated for the attribute “date of birth”, the external information source search unit 78 extracts data from both information sources.

変 換 The conversion specification is not given by the user for the attribute “birth date” of the data in the employee table 402. Therefore, the data conversion unit 76 does nothing, and the index is generated by the index generation unit 77 as it is.

On the other hand, in the case of the employee table 1004, the data format of the attribute “date of birth” is converted by the data conversion means 76. Here, it is assumed that the user has specified in advance that an attribute is to be generated for the attribute “date of birth” of the employee table 1004 by applying a program for converting the Japanese calendar to the Christian calendar. The data conversion means 76 converts the attribute “date of birth” of the data extracted from the employee table 1004 into the Christian era based on this information. Then, the index generation means 77 generates an index using the converted attribute value, the ID of the external information source 1003 (here, “2”) and the data ID, and stores the index storage unit 34 and the index value storage unit. Register to 35.

Through the above processing, the external information source 401 and the external information source 1003 can be searched using the same index.

[Embodiment 4]
Next, a fourth embodiment of the present invention will be described in detail with reference to the drawings.

Referring to FIG. 12, the fourth embodiment of the present invention includes a recording medium 11 on which an information search program is recorded. This recording medium 11 may be a magnetic disk, a semiconductor memory, or another recording medium.

The information search program is read from the recording medium 11 into the data processing device 12, and controls the operation of the data processing device 12. The data processing device 12 executes the following processing, that is, the same processing as the processing by the data processing device and the storage device in the first, second, and third embodiments under the control of the search program.

When an inquiry is given from the input device 1, first, the index information storage unit 33 is searched to determine whether an expression or an attribute in which an index is generated exists in the search condition expression of the inquiry. When indexes have been generated for all the expressions or attributes in the search expression, the index storage unit 34 is searched to determine the condition. If an attribute for which an index has not been generated is included, the inquiry processing is delegated to the external information sources 91 to 93.

If an index search has been performed, the search result is output next. At this time, the index information storage unit 33 is searched to check whether the output expression includes an expression or attribute for which an index has been generated. If indexes have been generated for all the expressions or attributes, the index value storage unit 35 is searched and an output is generated. When an attribute for which an index has not been generated is included, only data that satisfies the search condition is extracted from the external information sources 91 to 93, and a necessary value is extracted therefrom to generate an output.

。 The generated search result is displayed on the output device 4.

FIG. 1A is a block diagram illustrating a configuration of a conventional information search system, and FIG. 2B is a block diagram illustrating a configuration of an integrated information search system. FIG. 1 is a block diagram illustrating a configuration of a first exemplary embodiment of the present invention. 5 is a flowchart illustrating an operation of the first exemplary embodiment. FIG. 4 is a diagram illustrating a specific example of an operation according to the first exemplary embodiment. It is a block diagram showing composition of a 2nd embodiment of the present invention. 9 is a flowchart illustrating the operation of the second embodiment. 9 is a flowchart illustrating the operation of the second embodiment. FIG. 14 is a diagram illustrating a specific example of an operation according to the second embodiment. FIG. 11 is a block diagram illustrating a configuration of a third exemplary embodiment of the present invention. 13 is a flowchart illustrating the operation of the third embodiment. FIG. 14 is a diagram illustrating a specific example of an operation according to the third embodiment. FIG. 14 is a block diagram illustrating a configuration of a fourth exemplary embodiment of the present invention.

Explanation of reference numerals

1 Input device 2, 12 Data processing device 3, 8, 13 Storage device 4 Output device 5 Integrated information search system 7, 10 Data processing device 11 Recording medium 21, 71 Search means 22, 74, 77 Index generation means 30 Actual data Storage unit 31, 34, 403, 702, 1001 Index storage unit 32, 35, 408, 703, 1002 Index value storage unit 33, 701 Index information storage unit 51 Search mediation means 61, 62, 63 Information search system 73, 78 External Information source search means 75 Formula calculation means 76 Data conversion means 91, 92, 93, 401 External information sources 211, 711, 715 Search formula evaluation means 212, 712, 716 Output formula evaluation means 213, 717 Index search means 214 Real data search Means 402, 1004 Employee table 404, 1005 Name index 405, 1006 Date of birth index 406, 1007 Position index 407 Affiliation index 409, 706, 1009 Index value table 704 Index information table 7 13,718 Index value acquisition means 1003 Information source 2
1008 Age Index

Claims (3)

Data conversion means for converting attribute values in a plurality of information sources into a predetermined unified format,
Index generation means for generating an index for the value converted by the data conversion means,
Index search means for performing an index search using the index generated by the index generation means,
Search expression evaluation means for performing a condition search specified by a query using the index search means,
An information retrieval system comprising: Data conversion means of the information retrieval system converts attribute values in a plurality of information sources into a predetermined unified format,
The index generation means of the information search system generates an index for the value converted by the data conversion means and stores the index in the storage device of the information search system,
The index search means of the information search system performs an index search using the index generated by the index generation means,
An information search method, wherein the search expression evaluation means of the information search system performs a condition search specified by a query by the index search. A data conversion process of converting attribute values in a plurality of information sources into a predetermined unified format,
An index generation process for generating an index for the value converted by the data conversion process,
An index search process for performing an index search using the index generated by the index generation process;
A search expression evaluation process for performing a conditional search specified by a query using the index search process;
Recording medium storing a program for causing a computer to execute the program.

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