Hitachi, Ltd.

Other

Hitachi Software Engineering Company, Ltd.

Hitachi Microcomputer Engineering, Ltd.

Kazuo Masai

Masashi Tsuchida

Shunichi Torii

Kota Yamaguchi

Kiyomi Hirohata

Keisuke Toda

Hideaki Kasao

Nobuo Kawamura

Shoji Yamamoto

Takashi Sumiyoshi

Masaru Kitsuregawa

Satoshi Wakayama

Masao Makino

Yoshifumi Takamoto

Masaaki Iwasaki

Shinji Fujiwara

Nobuyuki Yamashita

Itaru Nishizawa

Kazutomo Ushijima

Kimitoshi Yamada

Ikuo Kimura

Tetsuo Saito

Tomihiko Kojima

Yori Takahashi

Mitsuo Miyazaki

Takayoshi Shimokawa

Hiroshi Nagai

Toshiharu Shinozaki

Kuniaki Yamashita

Hiroshi Takayama

A method and a system of database divisional management for use with a parallel database system comprising an FES (front end server), BES's (back end servers), an IOS (I/O server) and disk units. The numbers of processors assigned to the FES, BES's and IOS, the number of disk units, and the number of partitions of the disk units are determined in accordance with the load pattern in question. Illustratively, there may be established a configuration of one FES, four BES's, one IOS and eight disk units. The number of BES's is varied from one to four depending on the fluctuation in load, so that a scalable system configuration is implemented. When the number of BES's is increased or decreased, only the management information thereabout is transferred between nodes and not the data, whereby the desired degree of parallelism is obtained for high-speed query processing.

Method and system of database divisional management for parallel database system

Bookmark information indicative of a time corresponding to a given time series data piece for a predetermined time, state transition information indicative of a state of the time series data piece for the predetermined time, and the time series data piece are loaded in a database. The state transition information has one of a value indicative of an online state, a value indicative of a loading state, and a value indicative of a state in which data in the data area is empty. The time series data pieces for the predetermined times are loaded in a plurality of data areas of the database in sequence of times. In accordance with a data deletion request, state transition information corresponding to a data piece of information corresponding to a data piece of interest is set to a value indicating that the data piece of interest is empty.

Data structure in database, database system for managing database and database managing method and system

Judgement is made to determine whether or not an access request from a host computer is a write request and whether or not the contents of the write request are log information indicating contents of database processing executed in a buffer by the host computer. When the contents of the write request are the log information, position information indicated in the log information is converted into physical position information in a primary storage system using a conversion table indicating a correspondence between logical position information recognized by the host computer and physical position information in the primary storage system. According to the contents of the log information, data is updated in a database area of the primary storage system represented by the physical position information converted using the conversion table. The access request is sent to a secondary storage system.

Disaster recovery processing method and apparatus and storage unit for the same

A parallel database management system with a database divided into a plurality of external memory units is disclosed. A control CPU, upon receipt of a request for access to the database, decides whether the access request is for storing or searching a record. For a record storage request, the control CPU determines an external memory unit to store the record using a hash function. In the case of a record search request, on the other hand, all the external memory units are searched in parallel without using the hash function thereby to obtain the desired record. The hash function is altered upon addition of an external memory unit.

Parallel database record distribution method and parallel database management system

A parallel data base management system with a data base divided into a plurality of external memory units is disclosed. A control CPU, upon receipt of a request for access to the data base, decides whether the access request is for storing or searching a record. For a record storage request, the control CPU determines an external memory unit to store the record using a hash function. In the case of a record search request, on the other hand, all the external memory units are searched in parallel without using the hash function thereby to obtain the desired record. The hash function is altered upon addition of an external memory unit.

Parallel data base record distribution method and parallel data base management system

A method and a system of database divisional management for use with a parallel database system comprising an FES (front end server), BES's (back end servers), an IOS (I/O server) and disk units. The numbers of processors assigned to the FES, BES's and IOS, the number of disk units, and the number of partitions of the disk units are determined in accordance with the load pattern in question. Illustratively, there may be established a configuration of one FES, four BES's, one IOS and eight disk units. The number of BEST's is varied from one to four depending on the fluctuation in load, so that a scalable system configuration is implemented. When the number of BES's is increased or decreased, only the management information thereabout is transferred between nodes and not the data, whereby the desired degree of parallelism is obtained for high-speed query processing.

Method of executing partition operations in a parallel database system

Parallel data base record distribution method and parallel data base

A query issue processing method, a query conversion processing method, and a data control processing method are provided for enhancing the efficiency of random sampling processing for use in a database processing system. In query issue processing 2, a query including random sampling processing is issued. In query conversion processing 8, application sequences of random sampling processing and another query processing are exchanged by considering a sampling unit of the random sampling processing. Further, in record control processing 4, random access to a secondary storage device is reduced, thereby enhancing random sampling processing efficiency. Unlike the conventional query conversion processing not considering the sampling unit, the issuance of the query including random sampling processing and performing query conversion by considering the sampling unit allow random sampling to be applied also to a query including aggregation processing, thereby enhancing the efficiency of queries in a wider range. Reduction in the random access to the secondary storage device further enhances that efficiency.

Random sampling method for use in a database processing system and a

Method and system of database divisional management for parallel

In a database management method and a database management system in which transactions need not be stopped at a synchronization point (syncpoint) acquired at a fixed interval of time, when a point to acquire a syncpoint is reached in a database control procedure, a syncpoint acquisition start log is output and then a syncpoint acquisition flag is set ON in a page control table of each updated page existing in a buffer pool. In the operation, a list of update page control tables is also created to write in the database the pages which are indicated in the list thus prepared. However, for a transaction accessing the pertinent updated page prior to the write operation thereof in the database, the data write operation is performed before the page is referenced, thereby enabling the access to be performed to the database without interrupting the transaction.

Method of processing a synchronization point in a database management

A database system is provided for reading data from a database to a database buffer and performing a physical sequential scan for the data on the buffer. If the preceding request for physical sequential scan is under execution, the database system operates to keep the succeeding request for scan in a waiting state until the preceding requested scan is completed and then execute the succeeding request for scan after the preceding requested scan is completed. If there are more than one succeeding requests for physical sequential scan, they are executed at the same time. Another scanning method is also provided. If the preceding request for scan is under execution, the succeeding requested scan is executed for the data existing after the halfway location at which the preceding scan process now reads the data. The short data is read from its head for completing the subsequent scan.

Method for concurrently performing a physical sequential scan of a

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Yokohama, Japan

Kazuo Masai