Abstract: An image forming apparatus includes a photosensitive drum, a charging member, a developing member, a transfer member, first and second gears, a drive source, and a control unit. The charging member contacts the photosensitive drum and forms a charging portion to charge a surface of the photosensitive drum. The control unit performs control in such a manner that an image forming operation of performing image formation by rotating the photosensitive drum at a first rotational speed is executable. Where the control unit executes the image forming operation, the control unit performs a switch operation of stopping the photosensitive drum in a state in which the photosensitive drum is driven, while a non-image forming operation to be executed after the image forming operation is executed, and rotationally driving the photosensitive drum again at a second rotational speed faster than the first rotational speed, a plurality of times.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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 “update content being reflected”, each system searches the database or the update buffer and then returns the post-update data content to the terminal device.

Abstract: 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 “update content being reflected”, each system searches the database or the update buffer and then returns the post-update data content to the terminal device.

Abstract: Provided is a computer system including: an active system; and a standby system. The active system generates, when an update request is received, an after-update log, and sends the after-update log to the standby system at a predetermined timing. The standby system generates a before-update log based on the after-update log sent from the active system and the stored data, updates, after the before-update log is generated, the stored data based on the after-update log, and rolls, when a rollback request is received, the data back to the data before update based on the generated before-update log. Accordingly, it becomes possible to suppress an increase in period of time to reflect the data updated in the active system on the standby system, and to suppress an increase in period of time for rollback of the data performed in the standby system.