Hitachi, Ltd.

Shinsuke Hamada

Kouji Kimura

Yasuhiro Tahara

Akira Shimizu

Shinji Fujiwara

Norihiro Hara

Yuki Yamada

Akira Itou

Takayuki Tsuchida

Wataru Kawai

Kohei Isomatsu

A database management system receives a new data table input to a database; and executes unique constraint determination processing of determining whether each comparison-subject value as each value registered in a target column in the new data table is different from each comparison reference value as each value registered in a target column in a stored data table in the database, and stores the new data table in a second database area different from a first database area storing the stored data table in the database when a determination result obtained in the unique constraint determination processing is true.

Database management system and database management method

A database system comprises an interface for a storage device, and a control device for accessing the storage device through the interface. The storage device stores a table that manages a plurality of rows comprising a plurality of item values, and an index configured in a tree structure based on a plurality of nodes enabling to identify the rows by using one or more item values. The control device identifies an item value condition included in a search condition of a search query, determines whether or not the node of the index corresponding to the item value condition is reference-disabled, and when the node is reference-disabled, identifies a range of item values managed by the reference-disabled node, and searches for a row that satisfies the search condition for the identified range.

Database system and database management method

A DBMS is configured to identify a Boolean expression and conditional expressions from a search query, and to extract for each of the identified conditional expressions the value of a record ID conforming to a conditional expression. The DBMS is configured to change a conformity result value corresponding to the extracted record ID and conditional expression to a first value signifying conformity, in Boolean expression determination information, which is information that includes a determination set having a record ID value and a plurality of conformity result values respectively corresponding to a plurality of conditional expressions, and, on the basis of the Boolean expression, to perform logical operations on the plurality of conformity result values of a determination set, for each determination set in the Boolean expression determination information.

System, apparatus, and method for executing a query including boolean and conditional expressions

An execution system executes an update batch according to an update batch execution request from a terminal device and gives a batch execution command to each standby system. Each system stores the content of updated data in its update buffer; and subject to termination of the update batch by each system, the post-update data content is reflected in a database. While the above processing is performed, the execution system and the standby systems accept a reference request from the terminal device; and in a case of 'batch not executed' or 'batch in execution', each system searches the database and then returns the pre-update data content to the terminal device; and in a case of &#x201c;update content being reflected&#x201d;, each system searches the database or the update buffer and then returns the post-update data content to the terminal device.

System for judging an execution status of batch processing, and based on judgement result to send post-update data to terminal device

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Tokyo, Japan

Shinsuke Hamada