JPH09167167A - Object Retrieval Method in Object-Oriented Database - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To reliably and efficiently retrieve only an object having a specified member from all objects existing in a hierarchy below a specified class. An object is composed of information corresponding to an attribute and a class to which an object having an attribute and having an attribute of its own belongs, and the class has at least the attribute of its own. By assigning a class as a subordinate class, in an object-oriented database that constitutes a class hierarchy, when searching the database by designating the class and the attribute, information on the correspondence relationship between the class and the attribute and the class hierarchy. An object search method in an object-oriented database for selecting only a class having a specified attribute among a specified class and classes lower than the specified class as a search target class based on structure information.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an object search method in an object-oriented database using a computer.

[0002]

2. Description of the Related Art Most conventional databases use a database management system called a hierarchical type or a relational type. Such a conventional method is mainly used in the field of business processing which handles a large amount of data having a relatively simple structure. Among these, a relational database management system is widely used, which uses a simple data structure that can be represented in a tabular form and retrieves / operates data by a relational operation between tables.

However, when the hierarchical or relational database management system is applied to the fields of CAD, CASE, image processing, multimedia processing, etc., it is difficult to develop a database because of the following problems. Also, in terms of processing efficiency, it is often not always a good idea to create a database.

(A) The data structure of each data element is complicated and cannot be directly expressed in the data definition format provided by the database management system. (B) The definition of data and the operation designation are complicated because the data are intricately related to each other, and the processing efficiency for performing search / comparison on all data is poor.

(C) The database management that provides the data definition / manipulation function is an independent system itself, and its main usage is interactive execution with humans. Therefore, it is difficult to build a processing system that combines programs such as database processing and calculation processing.

An object-oriented database has been proposed, developed and used as a solution to these problems. Object-oriented database is a C language C
Many of them add database management functions based on existing object-oriented programming languages such as ++ and Smalltalk.

In object orientation, classes having slightly different properties are connected in a class hierarchy. For example, the class "Employee" and "Manager", "Manager",
Considering the class “general”, the “general manager”, “section manager”, and “general” classes have slightly different properties from “employee”, and the “employee” has a more general property. From the viewpoint of the “member” class from the upper class and the “employee” class, “department manager”, “section manager”, and “general” having more special properties can be considered as the lower class.

This upper and lower relationship is called a class hierarchy. Here, inheritance means that the lower class inherits the property of the upper class. With inheritance, when describing the properties of the lower class, only the differences from the lower class need be described. Using the inheritance relationship of the class hierarchy has the advantage that programs can be written efficiently, and is one of the important concepts of object orientation.

[0009]

In the above-mentioned object-oriented database, normal objects are searched for only one class. Therefore,
When there are a plurality of classes and a plurality of class hierarchies, the user has to search for each class that is likely to be related to the information to be searched. This approach is problematic in terms of search efficiency and certainty.

On the other hand, for example, when there is a class hierarchy,
It is possible to specify the upper class at the time of search and extend the search target from the upper class to the lower class. In this case, the amount of search targets becomes enormous, which is inefficient and requires time for search.

Further, if there is a common member (attribute) indicating the property of the class among the classes having a hierarchical relationship, a method of providing the common member as an index when searching an object in advance is considered. To be

However, in the case where one attribute (member) common to the classes having the class hierarchy is provided with one index, there are the following problems. -Since only the attributes common to the classes are provided as an index, this index is not suitable when searching for partial classes, that is, classes that do not have common attributes.

It is necessary to prepare indexes of all combinations in advance, which makes the management of indexes large. -Uncommon attributes cannot be included in the index target.

As described above, each of the conventional methods has various problems, and it is an object of the present invention to solve these problems and establish an efficient object search method including a subclass as a search target. This is a technical issue.

That is, the present invention has been made in consideration of such a situation, and when there is a class hierarchy in an object-oriented database, it is specified from all the objects existing in the hierarchy below the specified class. An object of the present invention is to provide an object search method in an object-oriented database that enables reliable and efficient search of only objects that have members.

[0016]

In order to solve the above-mentioned problems, the invention according to claim 1 is provided with an object consisting of at least one attribute information corresponding to an attribute, at least one attribute, and own. It is composed of a class to which the object having attributes is attached, and the class is made to belong to a class having at least the attributes of its own as a subordinate class,
In an object-oriented database that constitutes a class hierarchy, when searching the database by specifying at least a class and an attribute, it is specified based on the information on the correspondence relationship between the class and the attribute and the information on the hierarchical structure of the class. Out of the following classes and lower classes
It is an object search method in an object-oriented database in which only a class having a specified attribute is selected as a search target class.

The invention according to claim 2 is the invention according to claim 1, in which the target class for the search is selected so that at least the lower class can belong to which the corresponding lower class can be searched using the attribute as an index. It is an object search method in an object-oriented database, which is performed using hierarchical index information provided for each class.

Further, the invention according to claim 3 is the invention according to claim 1 or 2, wherein when an object, a class, or an object can be added, changed, or deleted, if the object is added, changed, or deleted, Object-oriented that enables selection of search target classes even after addition, modification, or deletion by modifying the information on the corresponding relationship between corresponding classes and attributes and the information on the hierarchical structure of classes, or the corresponding hierarchical index information. It is an object search method in a database.

Therefore, first, in the object search method in the object-oriented database of the invention according to claim 1, the object-oriented database has a hierarchical structure, and an attribute including an attribute of the class is under a certain class. It is configured to belong to a class having.

When at least a class and an attribute of a database having such a hierarchical structure are designated and searched for, a designation is made based on the information on the correspondence between the class and the attribute and the information on the hierarchical structure of the class. Of the class and classes lower than the class, only the class having the specified attribute is selected as the search target class.

Therefore, it is possible to reliably and efficiently retrieve only the object having the designated member (attribute) from all the objects existing in the hierarchy below the designated class.

Further, in the object search method in the object-oriented database of the invention according to claim 2, the same operation as the invention according to claim 1 is performed, and the selection of the search target class is performed by using the attribute as an index. It is performed using the hierarchical index information provided for each class having a lower class that can retrieve the lower class.

Therefore, the class to be searched can be selected more efficiently. Furthermore, in the object search method in the object-oriented database of the invention corresponding to claim 3, when the object or class can be added, changed or deleted in addition to the same function as the invention corresponding to claim 1 or 2, When added, changed or deleted, the information on the corresponding relationship between the corresponding class and attribute, the information on the hierarchical structure of the class, or the corresponding hierarchical index information is corrected. Therefore, even after the addition, change, or deletion, the target class for the search can be surely selected.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. (First Embodiment of the Invention) FIG. 1 is a block diagram showing an example of an object-oriented database to which an object search method according to a first embodiment of the present invention is applied.

This object-oriented database includes a request processing section 3, an instance management section 4, and a data area 5.
The database 6, the database management unit 7, the class information management unit 8, the class Ci management unit 10 provided in the instance management unit 4, and other peripheral elements (not shown).

The request processing unit 3 uses the object search request 1
Is input, the search information is obtained in cooperation with the class information management unit 8 based on the conditional expression included in the request, and the search results obtained by the instance management unit 4 are collected based on the search information. Or other specified form is output as the search result 2.

Here, a set is a collection of all objects. Further, as another example of the specified form, there is, for example, displaying all the attribute information contents of one object matching the search condition. In the present embodiment, a case where a set is returned as a search result will be described.

The request processing unit 3 first analyzes the conditional expression and creates search information. FIG. 2 is a block diagram showing a configuration example of the request processing unit and the class information management unit 8 in the object-oriented database of the same embodiment.

As shown in FIG. 3A, the request processing unit 3
Is the search information 1 from the set creation unit 12 and the condition analysis unit 13.
Create 4. The condition analysis unit 13 analyzes the conditional expression,
The following items are taken out.

Class ID (ID indicating the class initially specified in the conditional expression. Here, class ID = Ci is assumed to indicate any class ID) Member ID (specified in the conditional expression ID indicating a member (attribute). Here, member ID = Mi) -Comparison operator (for example, operators such as large, small, and equal) -Key value (for searching corresponding to the member and comparison operator) There are multiple values depending on the target value and the comparison operator) -Restrictions (additional conditions such as multiple search results required, class restrictions on search targets) Note that Ci is the object ID attached to the class existing in the database. That is, the OID is specifically called a class identifier (class ID).

The set creation unit 12 is an object ID,
That is, a set for storing the OID is created. However, if the constraint is that there is only one search result, it is not necessary to create a set. The storage of this OID is performed in order to output the detection result.

The request processing unit 3 uses the class ID and the member ID previously obtained, and the member ID is Mi in the lower class from the hierarchical structure information 15 and the class configuration information 16 which will be described later in the class information management unit 8. Ask for classes that have members. Including this and the class whose class ID is Ci, the class actually having the member ID, Mi in the object is set as the search target range.

Here, the object is a minimum unit of a database that stores information, values, etc. corresponding to various items (members) corresponding to the object OID. On the other hand, the member (attribute) indicates each of the above items stored in the object.

Further, each class has information indicating what kind of member the object belonging to the class or the class belonging to the class has. That is, the information of members in this class is provided in the form of inheritance as described in the related art, and is not duplicated in each class. Therefore, the members also indicate the properties of the class. In addition, each class constitutes a class hierarchy as described in the related art.

Therefore, an object is registered in the class as an object belonging to the class when all the members of the object match the members of the class summed up by inheritance.

Such class information is provided in the class information management unit 8, and the class information management unit 8 shown in FIG.
The configuration is as shown in (b). The class information management unit 8 includes a hierarchical structure information 15 and class configuration information 16
And class structure information 17 are provided, and these pieces of information are created, changed and deleted at the time of class (object) creation / deletion / change request 9. Each of these configurations is shown in FIGS.

FIG. 3 is a diagram showing the hierarchical structure information 15 of the object-oriented database of this embodiment. FIG. 4 is a diagram showing class configuration information and class structure information of the object-oriented database of this embodiment.

In FIGS. 3 and 4, each information is shown in a tabular form for simplification, and the class configuration information 16 and the class structure information 17 are collectively shown. First,
In FIG. 3, the hierarchical structure unit 15 is provided with a list of class IDs (identifiers) of superclasses and class IDs (identifiers) of subclasses for the classes. Here, when there is a class hierarchy, the superclass means a class higher than the class, and the subclass means a class lower than the class. In FIG. 3, a superclass / class identifier list 18 and a subclass / class identifier list 19 corresponding to a certain class are shown.

On the other hand, as shown in FIG. 4, the class configuration information 16 and the class structure information 17 include a class identifier 20 (class ID), a member identifier 21 (member ID), a member type 22, and physical information 23. Composed of. Here, the member type 22 indicates the type of data of the physical information 23, and the physical information 23 stores information about the actual physical structure such as the storage position of the corresponding member.

As described above, the class information management unit 8 stores the correspondence relationship between each class and its members, and the upper and lower correspondence relationships between the classes.
As described above, the request processing unit 3 can detect the class having the member ID Mi in the lower class by using the class ID, Ci and the member ID, Mi obtained from the conditional expression. In this case, the class ID is used as an index to check whether or not there is a member ID or Mi to be searched, and if there is Mi, the class is detected.

In some cases, for example, information for limiting the class may be given in advance to the restrictions, so that each class except the class restricted by the restrictions from the detected class and the class ID and the class Ci. , And the range of the search target class.

The request processing unit 3 also creates search conditions. This is created from the member ID, Mi, the comparison operator, and the key value. For example, in a database that handles "vehicles", "cars (class)" of "horsepower (member) 200 (key value) or more (comparison operation value)". If it is a conditional expression of the content, the search condition will be content such as “horsepower ≧ 200”.

Therefore, the finally created search information 14 includes the search condition, the range of the search target class, and the OID.
And a set for storing. In addition, as a part of the search information, information about the class of the search target range is also added.

Next, each part for searching the object OID based on the search information 14 will be described. The instance management unit 4, that is, the object management unit,
The class Ci management unit 10 provided for each class is provided, and the OID of the requested object is obtained from the classes having the hierarchical relationship according to the search information obtained by the request processing unit 3.

Specifically, from the class of the search target range,
An unsearched class is selected, an object of the selected class is searched from the data area 5, and the OID of the object that matches the search information such as the search condition is registered in the set of search information as the search result.

Each class Ci management unit 10 manages the objects of the class in charge for each class. That is, the object 11 of each class is managed by the index for each class.

For example, in the class Ci management unit 10, the member value is the same as the key value (depending on the comparison operator, it is indicated as the key value) from the member identifier (member ID, for example, member name), the key value, and the comparison operator. It is possible to retrieve the OID of an object (which is in the range specified).

Further, the class Ci management unit 10 updates the index at the time of request 9 for creating / deleting / changing an object of the class. The data area 5 stores objects 11, which are stored in the instance management unit 4
Will be the search target from.

The database 6 also stores the object 11 and information and classes managed by each management unit as an object. Note that Ci (1 ≦ i ≦ N, N is the total number of classes registered in the database) represents any class ID of the classes included in the database 6. The database 6 is specifically composed of a large-capacity storage medium such as a hard disk, and stores each information of the database.

The database management unit 7 follows the class information management unit 8 in accordance with the object generation / deletion / modification request 9.
It manages the instance management unit 4, the data area 5, and the OID uniquely determined for all objects.

That is, each part is also managed, and for example, in order to ensure high-speed operation of the system, the object 1 stored in the database at the time of system startup is
1 is copied to the data area 5. In addition, necessary management operations are performed according to the operation of each unit.

Next, the operation of the object-oriented database to which the object search method according to the embodiment of the present invention configured as described above is applied will be described with reference to the flowchart of FIG.

FIG. 5 is a flow chart showing the operation of the object-oriented database of this embodiment. After the database is activated and the request can be accepted, first, the object search request 1 is input and the request processing unit 3
Then, the conditional expression is analyzed (ST101).

Next, the analyzed class ID and member ID
Based on the above, the range of the search target class is detected from the hierarchical structure information 15 and the class configuration information 16 in the class information management unit 8, a search condition and a set of search information are created, and the search information 14 is created from them. (ST102).

Here, each search target class includes a designated class ID, Ci, and whether or not there is a designated member ID, Mi for each class from all lower classes. Is examined and detected.

Next, the instance management unit 4 starts the search for the target object. First, it is determined whether or not there is an unsearched class among the search target classes (ST103). If there is no unsearched class, the search ends. If there is an unsearched class, the search target class range is set. An unsearched class is selected (ST104).

Next, in that class, a search is performed,
It is determined whether or not the search condition is satisfied for each object 11 (ST105). If there is an object that satisfies the search information such as the search condition, the OID of the object is registered in the set of search information (ST106), and the search information is updated (ST107), that is, the next search target class Searched, step ST
Returning to 103, the search is continued as long as there is an unsearched class among the search target classes.

When the search is completed, the set of objects corresponding to the OID registered in the set of search information is changed to
The search result 2 is output from the request processing unit 3. As described above, according to the object-oriented database and the object search method therefor according to the embodiment of the present invention, the member designated from the classes having the class ID or less designated by the hierarchical structure information 15 and the class configuration information 16 is included. Since only the class having the ID is specified as the search target class and only the objects belonging to the search target class are set as the search target of the search condition, even if the class has a hierarchy, the specified class is specified. It is possible to reliably and efficiently retrieve only the object having the specified member from all the objects existing in the hierarchy below the class.

As a result, it is possible to automatically perform a search process that a user conventionally has to perform across a plurality of classes. Especially, when the class structure is complicated, the description amount of the user's search request can be reduced. Can be significantly reduced.

Further, since the index used for searching the object is managed on a class-by-class basis, the index can be used as it is even when searching by class alone, and management is simple. It should be noted that in the present embodiment, the object itself can be searched for, that is, searched without calling.

As a matter of course from the configuration operation of the present invention, it is possible to deal with a search for a member that is not common to the lower classes. (Second Embodiment of the Invention) In this embodiment, hierarchical index information is added to the class information management unit 8 of the object-oriented database of the first embodiment of the invention to make the range of search target classes more efficient. It is the one that was asked for.

That is, the object-oriented database of the present embodiment is constructed in the same manner as in the case of the first embodiment, except that the hierarchical index information shown in FIG. 6 is used in the method of obtaining the range of the search target class. It

FIG. 6 is a diagram showing the class information management unit 8 of the object-oriented database to which the object search method according to the second embodiment of the present invention is applied. The class information management unit 8 is provided with hierarchical structure information 15, class configuration information 16, class structure information 17, and hierarchical index information 24 shown in FIG.

Here, the hierarchical structure information 15, the class structure information 16, and the class structure information 17 are configured in the same manner as in the first embodiment, but they are used to obtain the range of the search target class. Not done.

FIG. 7 is a block diagram showing the hierarchical index information 24 of the object-oriented database according to this embodiment. The hierarchy index information 24 includes two sets of attribute lists 25 #.
1 and 25 # 2.

Each of the attribute lists 25 # 1 and 25 # 2 is constructed so that the class identifier list 27 can be searched using the member identifier 26 as an index. Further, both attribute lists are provided corresponding to all classes, and the class identifier list 27 to be searched is only a class lower than its own class.

In the attribute list 25 # 1, the class identifier list 27 is the lowest class ID list that has no lower class than the corresponding class. On the other hand, in the attribute list 25 # 2, the class identifier list 27 is a class ID list of classes that may have subclasses lower than the corresponding class.

The configuration examples of the other information managed by the class information management unit 8 are the same as those shown in FIGS. 5 and 6, and the information in each figure including FIG. It is expressed in the format.

Next, the operation of the object-oriented database to which the object search method according to the embodiment of the present invention configured as described above is applied will be described. The operation of the object-oriented database of this embodiment is the same as that of the first embodiment, except for the detection operation of the search target class, so only the operation of this part will be described.

In this case, in the search information creation ST102 in the flowchart of FIG. 5, the range of the search target class is
It can be obtained only by referring to the hierarchy index information 24 of the class information management unit 8.

That is, each attribute list 25 # 1 and 25 #
2, the class identifier list 27 can be searched using the member identifier 26 as an index, and the class corresponding to the class identifier list 27 is only the subordinate class of the specified class ID, Ci, so the hierarchy index information 24 is referenced once. The range of the search target class is decided by.

As described above, according to the object-oriented database and the object search method thereof according to the embodiment of the present invention, the search target class is selected by one search of the hierarchical index information 24. In addition to the effect similar to the embodiment, it is not necessary to carry out a sequential procedure using the hierarchical structure information 15 and the class configuration information 16 in selecting the search target class, and the search information can be efficiently obtained.

Therefore, the retrieval efficiency can be further improved. It can also handle search requests for members that are not common to lower classes. In the present embodiment, the attribute lists 25 # 1 and 25 # for all classes are listed.
2 is provided, but regarding this member identifier 2
It is also possible to search the entire class identifier list 27 by using 6 as an index, and use the hierarchical structure information 15 to exclude the upper class from the searched class.
By doing so, it is not necessary to provide an attribute list for each class. (Third Embodiment of the Invention) FIG. 8 is a block diagram showing an example of an object-oriented database to which an object search method according to a third embodiment of the present invention is applied. The same parts as those in FIGS. 4, 6 and 7 are designated by the same reference numerals and the description thereof will be omitted. Only different parts will be described here.

This embodiment is provided with a user-defined set management unit 28 that receives an object addition / deletion / modification request 29, and is the same as the object-oriented database of the first or second embodiment. Is configured.

Originally, in an object-oriented database described in C language or the like, it is not easy for a user to create a set and add / delete / modify objects by himself / herself. The user-defined set management unit 28 is for realizing easy addition / deletion / change of objects by the user.

The object-oriented database according to the present embodiment is the object-oriented database according to the first or second embodiment to which an easy addition / deletion / modification function of objects by the user is added. is there.

The object addition / deletion / change function will be described below. First, the user-defined set management unit 28
Accepts class definitions from the user. When the contents of each member are defined in this way, the user-defined set management unit 28 determines the hierarchical structure information 15, class configuration information 16, class structure information 17 corresponding to the class and hierarchical index information when the class structure information 17 is provided. 24 is created in the class management information section 8.

Next, the user-defined set management unit 28 generates an additional object therein by a user input before adding a new object to the database, gives an OID to this additional object, and associates the class. . At this time, if there is no corresponding class, a class is created by the class definition. The pair of the OID and the class identifier (ID) of the additional object is registered in the object generation information in the user-defined set management unit 28 (not shown).

When the user-defined set management unit 28 receives a request for adding an object, the user-defined set management unit 28 sets the O
The ID and the object generation information are used to search the class to which the object belongs and the corresponding class Ci management unit 10 in the instance management unit 4. If the corresponding class Ci management unit 10 does not exist, a new class Ci management unit 10 is created.

When the user-defined set management unit 28 detects the class Ci management unit 10 corresponding to the additional object, the user-defined set management unit 28 delivers the addition request to the class Ci management unit 10 together with the OID of the additional object.

The class Ci management unit 10 to which the addition request is delivered, the user-defined set based on the class configuration information 16 and the class structure information 17 of the class information management unit 8, especially the physical information 23 in the class structure information 17. The additional object generated in the management unit 28 is additionally registered in the data area 5.

When the user-defined set management unit 28 receives the object deletion request, the user-defined set management unit 28 delivers the object deletion request together with the OID corresponding to the deletion object to the class Ci management unit 10 of the corresponding class as described above.

The class Ci management unit 10 specifies the deletion object in the data area 5 based on the information of the class configuration information 16 and the class structure information 17, and deletes it.
Further, upon receiving the object change request, the user-defined set management unit 28 delivers the object change request together with the OID corresponding to the object to the class Ci management unit 10 of the corresponding class as described above.

The class Ci management unit 10 takes out a change object in the data area 5 based on the information of the class configuration information 16 and the class structure information 17, and stores it in a change area (not shown) in the user-defined set management unit 28. Make a copy. The user makes necessary changes to the changed object copied in the changed area and inputs the object change request again.

Thereafter, similarly to the case of adding an object, the class Ci management unit 10 updates the data area 5 with the changed changed object in the changed area.
Further, when the above addition / deletion / change operations are performed, the database management unit 7 that manages the operation of each unit performs the database at an appropriate timing based on the result of the addition / deletion / change of the object in the changed data area. Update the contents of 6.

When the above-mentioned addition / deletion / change operation is performed, the user-defined set management unit 28 corrects the corresponding class configuration information 16, class structure information 17, and hierarchical structure information 15, whereby the user The same search as in the case of the first embodiment can be executed for the database added / deleted / changed by.

In addition, in the case corresponding to the second embodiment, when the addition / deletion / change operation is performed, the corresponding hierarchy index information 24 is modified and the operation for the object search request 1 is secured. Become.

As described above, according to the object-oriented database and the object search method thereof according to the embodiments of the present invention, in addition to the configuration and operation of each of the above-described embodiments, the user can easily add / delete / add objects. Since the configuration is changeable, in addition to the same effects as in the above-described respective embodiments, it is possible to reliably select the search target class even after addition, change, or deletion.

Therefore, it is possible to provide an object-oriented database that is more user-friendly. The present invention is not limited to the above embodiments, and can be variously modified without departing from the gist thereof.

[0090]

As described above in detail, according to the present invention, only the class of the designated member is selected. Therefore, when there is a class hierarchy in the object-oriented database, the hierarchy below the designated class is selected. It is possible to provide an object search method in an object-oriented database capable of surely and efficiently searching only an object having a designated member from all the objects existing in the object.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an example of an object-oriented database to which an object search method according to a first embodiment of the present invention is applied.

FIG. 2 is a block diagram showing a configuration example of a request processing unit and a class information management unit in the object-oriented database according to the same embodiment.

FIG. 3 is a diagram showing hierarchical structure information of the object-oriented database according to the same embodiment.

FIG. 4 is a diagram showing class configuration information and class structure information of the object-oriented database according to the same embodiment.

FIG. 5 is a flowchart showing the operation of the object-oriented database according to the same embodiment.

FIG. 6 is a diagram showing a class information management unit of an object-oriented database to which the object search method according to the second embodiment of the present invention is applied.

FIG. 7 is a configuration diagram showing hierarchical index information of the object-oriented database according to the same embodiment.

FIG. 8 is a configuration diagram showing an example of an object-oriented database to which an object search method according to a third embodiment of the present invention is applied.

[Explanation of symbols]

1 ... Object search request, 2 ... Search result, 3 ... Request processing section, 4 ... Instance management section, 5 ... Data area, 6 ...
Database, 7 ... Database management unit, 8 ... Class information management unit, 9 ... Object creation / deletion / change request, 1
0 ... Class Ci management unit, 11 ... Object, 12 ... Set creation unit, 13 ... Condition analysis unit, 14 ... Search information, 15 ...
Hierarchical structure information, 16 ... class configuration information, 17 ... class structure information, 18 ... superclass / class identifier list,
19 ... Subclass / class identifier list, 20 ... Class identifier, 21 ... Member identifier, 22 ... Member type, 23 ...
Physical information, 24 ... Hierarchical index information, 25 ... Attribute list, 2
6 ... Member identifier, 27 ... Class identifier list, 28 ...
User-defined set management unit, 29 ... Object creation / deletion / modification request.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Ryuji Tanaka, No. 1 Toshiba-cho, Fuchu-shi, Tokyo Toshiba Corporation Fuchu factory

Claims (3)

[Claims] 1. An object comprising at least one information corresponding to an attribute, and at least one attribute,
A class to which the object having its own attribute information belongs is configured, and the class has a class hierarchy by having a class having at least its own attribute belong to a lower class. In the object-oriented database to be specified, when the database is searched by designating at least the class and the attribute, designation is made based on the information on the correspondence relationship between the class and the attribute and the information on the hierarchical structure of the class. A method for searching an object in an object-oriented database in which only a class having a specified attribute is selected as a target class for the search from the selected class and a class lower than the class. 2. The selection of the class to be searched is performed using hierarchical index information provided for at least each class to which the corresponding lower class can be searched by using the attribute as an index to search the corresponding lower class. Item 1. An object search method for an object-oriented database according to item 1. 3. When the addition, change or deletion of an object or class is possible, when the addition, change or deletion is performed, information on the corresponding relationship between the corresponding class and the attribute and the hierarchical structure of the class By modifying the information, or the corresponding hierarchical index information, the addition,
3. The object search method in an object-oriented database according to claim 1, wherein the target class of the search can be selected even after the change or deletion.