Fujitsu Corporation

Yoshio Mogi

Tadamitsu Ryu

Takanori Fukatsu

Gen Kakehi

Akira Hashimoto

Shingo Hirono

Masahiko Murakawa

Tohru Matsumoto

Toshio Takahara

Mamoru Endo

Masao Tomita

Mitsuhiko Yamagata

Takashi Ohshiro

Yasumasa Takahashi

Hiroshi Araki

Katsuo Sato

Hideyo Okazaki

A data retrieval method and apparatus in a distributed database system. Data is retrieved from a distributed database quickly with a minimum load on each terminal. A contents file is provided in each terminal, and a link file is provided in a center system to coordinate access to the distributed data in each terminal.

Distributed database system having a center system with a link file and

The system provides a data storage system program 18 between a user and a physical memory device 14 which stores file records 20. The data storage system 18 stores records as linked record segments 40/51 that can be randomly located within the memory storage device 14. The segments 40/51 are linked by a next segment address found in a next segment address field 50/56 of a record segment 40/51. When a record needs to be expanded and the current record segment 1000 is not large enough to accommodate the expansion, another record segment 1082 is allocated and used. If variable length record segments 40 are used, only a single record extension is required. However, if fixed length record segments 50 are used, the system allocates sufficient fixed length record segments to store the additional data. When records shrink in size or are deleted, the vacant space becomes available for reuse and the system attempts to remove the vacant space by combining record segments and storing a single segment in available vacant space.

Dynamic data storage system allowing variable size records and fields by

Network control system

The present invention is a system that converts a vertical file (28) of time series data records from multiple terminals (10-14) and stored by time into a horizontal file (52) where records are organized by terminal (10-14). The user can then access the desired terminal information rapidly in the horizontal file (52) rather than having to perform an inefficient sequential search of the vertical file (28). After the terminal data is horizontally stored, the data is used to create display or print-out windows of the terminal data for many locations. Each window includes the data from a single terminal (10-14). For example, each window could include a graph of rain data for a location. The system also creates a cross reference table (76) of the addresses of the data used to create each window. When the display arrangement is altered, the data in the horizontal file (52/74) is reorganized to match the display order while only the physical addresses of the data for each terminal are changed in a new cross reference table (80).

Sampled data storage and editing system for the time series data being

Distributed data base control center having a plurality of information

Growing community of inventors

Tochigi, Japan

Yoshio Mogi