Abstract: A method for rapidly executing a series of remote procedure calls between a client and a server, comprising an RPC optimizer (101) that inputs an IDL source code (103) and client source codes (102, 102?, . . . ) so as to define as a new remote procedure a group of remote procedures to be performed by the client in an additional server source code (107). In turn, the RPC optimizer outputs a new IDL source code (106) to which an interface of the remote procedure is added, and new client source codes (105, 105?, . . . ) modified so as to use the remote procedure. This reduces communications involving a plurality of remote procedures to a single communication pass, thereby implementing high-speed communication between the client and the server.

Abstract: A storage comprising an object access module for the shared part for implementing advanced I/O provides an interface for registering and deleting object description data declaring how to store objects within a second storage, in order to reduce the development cost of modules for implementing functions. Also, in order to reduce the total cost of ownership, modules are transferred to the storage through a management computer. The present invention allows the storage for contiguously providing functions effective to a vast range of applications to be provided with lower development cost as well as lower total cost of ownership.

Abstract: A storage comprising an object access module for the shared part for implementing advanced I/O provides an interface (121) for registering and deleting object description data declaring how to store objects within a second storage, in order to reduce the development cost of modules for implementing functions. Also, in order to reduce the total cost of ownership, modules are transferred to the storage through a management computer. The present invention allows the storage for contiguously providing functions effective to a vast range of applications to be provided with lower development cost as well as lower total cost of ownership.

Abstract: In order to realize a practical data warehouse system with the use of a network in a distributed environment, for example, data collectors for creating/managing each replica of server data for clients shown in FIG. 1 are connected to a network. A data collector holds a data request condition given from a user via a client and negotiates with a server which supplies data according to such resources as a storage unit, a CPU, etc., usable by the data collector, thereby the range and quality of the data for which a replica is to be created can be adjusted. For query processing, a part or the whole of a query from a client is processed with the use of a replica created in the data collector. Queries which cannot be processed with any replica in the data collector are transferred to the server. Because a replica created in the data collector can be used to process a query from a client in such a way, the server load can be reduced.

Abstract: In order to realize a practical data warehouse system with the use of a network in a distributed environment, for example, data collectors (101 and 102) for creating/managing each replica of server data for clients (103 and 104) as shown in FIG. 1 are connected to a network (113). A data collector holds a data request condition given from a user via a client and negotiates with a server (114, 122) which supplies data according to such resources as a storage unit, a CPU, etc. usable by the data collector, thereby the range and quality of the data for which a replica is to be created can be adjusted. For query processing, a part or the whole of a query from a client is processed with the use of a replica (123) created in the data collector. Queries which cannot be processed with any replica in the data collector are transferred to the server. Because a replica created in the data collector can be used to process a query from a client device such a way, the server load can be reduced.

Abstract: A method for rapidly executing a series of remote procedure calls between a client and a server, comprising an RPC optimizer (101) that inputs an IDL source code (103) and client source codes (102, 102?, . . . ) so as to define as a new remote procedure a group of remote procedures to be performed by the client in an additional server source code (107). In turn, the RPC optimizer outputs a new IDL source code (106) to which an interface of the remote procedure is added, and new client source codes (105, 105?, . . . ) modified so as to use the remote procedure. This reduces communications involving a plurality of remote procedures to a single communication pass, thereby implementing high-speed communication between the client and the server.

Abstract: The present invention relates to an optimization method in a database management system having the function of accessing external databases. Conventionally, whether functions contained in a query can be executed in external databases depends on a database management system having the functions, and therefore there has been a problem in that a database utilization method cannot apply to query optimization and query execution performance is reduced. To solve the above problem, a database management system having the function of accessing external databases is provided with an optimization step comprising the steps of: obtaining specification about whether to execute functions in a query in external databases; determining whether data referred to in a query is confined to one database; and determining whether a user specifies that the functions in the query are executed in external databases.

Abstract: A method for integrating data, stored not only in a relational database management system but also in data sources such as legacy application programs or tertiary storage where inquiry cannot be executed efficiently, and for performing inquiry quickly. A distributed index for use by a data source is generated in a database hub in advance, and a distribution index application unit converts and disassembles an inquiry using the distributed index.

Abstract: Method and apparatus for query processing including an optimization controller, responding to a query from an application related to an database, and controlling optimization processing of the query. A query classification definition and a query operation direction associated with the query classification definition are defined on a storing means. The query classification definition classifies the queries according to classifications and attributes including environment for use, time for use, database to be accessed, and the amount of data that is processed. The query operation direction defines strength of the direction including “Force”, “Recommended”, “Neutral”, and “Deny”, which is used to select operation at the time of query execution from several alternatives.

Abstract: A query processing system in which a virtual table to enable multiple mapping to a plurality of databases is provided in a data processing system to receive a query from an application program and partial replicas as copies of part of the data in the virtual table is prepared in storage so that the whole or part of a query can be processed using the partial replicas. For query units which cannot be processed using the partial replica, means to select an appropriate distributed join method and optimization to push down query processing to real databases as far as possible are used. The system allows transparent access to multiple different real databases according to access conditions without changing the column to be accessed in the virtual table or switching the virtual table, thereby eliminating the need to create a new application for each newly developed service.

Abstract: In order to perform format conversion between the formats of a plurality of files without any work by a user, a file system stores a relation between a conversion originating file and a conversion destination file, and synchronously with an issue of a file operation API, the format conversion processes are executed. A user performs only the tasks essential for an application, without taking into consideration various necessary format conversions (either one-step or multi-step). During the user task, it is not necessary to designate a conversion originating file and a timing of format conversion. A user can use always a latest conversion destination file.

Abstract: A data request analysis unit for accepting and analyzing a request from a client computer, a data conversion program generation unit, and a data conversion unit are provided in a magnetic disk apparatus, the data conversion program generation unit downloads a program module by way of a network as required based on the analysis result obtained by use of the data request analysis unit to generate a data conversion program, and the data conversion unit downloads the conversion program, and converts the type of the data read out from the magnetic memory medium by use of the program, and directly transfers the converted data to the client computer by way of a network interface, thereby, the present invention provides a general purpose magnetic disk apparatus which is capable of flexibly accommodating the request from the client computer, the scalability of the whole system is improved because the data is converted in the magnetic disk apparatus, and the process efficiency of the client computer is improved.

Abstract: The present invention relates to an optimization method in a database management system having the function of accessing external databases. Conventionally, whether functions contained in a query can be executed in external databases depends on a database management system having the functions, and therefore there has been a problem in that a database utilization method cannot apply to query optimization and query execution performance is reduced. To solve the above problem, a database management system having the function of accessing external databases is provided with an optimization step comprising the steps of: obtaining specification about whether to execute functions in a query in external databases; determining whether data referred to in a query is confined to one database; and determining whether a user specifies that the functions in the query are executed in external databases.

Abstract: In order to perform format conversion between the formats of a plurality of files without any work by a user, a file system stores a relation between a conversion originating file and a conversion destination file, and synchronously with an issue of a file operation API, the format conversion processes are executed. A user performs only the tasks essential for an application, without taking into consideration various necessary format conversions (either one-step or multi-step). During the user task, it is not necessary to designate a conversion originating file and a timing of format conversion. A user can use always a latest conversion destination file.

Abstract: In order to perform format conversion between the formats of a plurality of files without any work by a user, a file system stores a relation between a conversion originating file and a conversion destination file, and synchronously with an issue of a file operation API, the format conversion processes are executed. A user performs only the tasks essential for an application, without taking into consideration various necessary format conversions (either one-step or multi-step). During the user task, it is not necessary to designate a conversion originating file and a timing of format conversion. A user can use always a latest conversion destination file.

Abstract: A method for integrating data, stored not only in a relational database management system but also in data sources such as legacy application programs or tertiary storage where inquiry cannot be executed efficiently, and for performing inquiry quickly. A distributed index for use by a data source is generated in a database hub in advance, and a distribution index application unit converts and disassembles an inquiry using the distributed index.

Abstract: In order to perform format conversion between the formats of a plurality of files without any work by a user, a file system stores a relation between a conversion originating file and a conversion destination file, and synchronously with an issue of a file operation API, the format conversion processes are executed. A user performs only the tasks essential for an application, without taking into consideration various necessary format conversions (either one-step or multi-step). During the user task, it is not necessary to designate a conversion originating file and a timing of format conversion. A user can use always a latest conversion destination file.

Abstract: In order to effectively make the grasp of operating conditions of a plurality of servers and a cache management in an information system without increasing a time/labor taken by an administrator, the plurality of servers forms a multi-cast hierarchy dynamically reconstructed by virtue of mutual support and the communication of server status, cache directory and validation is performed on the hierarchy. The administrator has not a need of management for cooperation between servers excepting the designation of some other servers for startup thereof. A cache between servers is shared through the exchange of a cache directory and a validation time is reduced, thereby shortening the response time for users.

Abstract: In order to perform format conversion between the formats of a plurality of files without any work by a user, a file system stores a relation between a conversion originating file and a conversion destination file, and synchronously with an issue of a file operation API, the format conversion processes are executed. A user performs only the tasks essential for an application, without taking into consideration various necessary format conversions (either one-step or multi-step). During the user task, it is not necessary to designate a conversion originating file and a timing of format conversion. A user can use always a latest conversion destination file.

Abstract: Irregular and unstable natures of the Internet to be caused by an increase in Internet accessing users are alleviated and services of an information system more comfortable to users are provided. To this end, each servers among a plurality of servers cooperating to provide services stores the past communications line state (throughput and latency), and in accordance with the stored communications lines state, cache reference and prefetch are preformed between optional servers.