Abstract: A database management system (DBMS) generates a query execution plan including information representing one or more database (DB) operations necessary for executing a query, and executes the query in accordance with the query execution plan. In the execution of the query, the DBMS dynamically generates tasks for executing the DB operations and executes the dynamically generated tasks. The query execution plan includes a plurality of query blocks, which are sets of one or more DB operations. When newly generating a task, the DBMS executes determination processing of simultaneous-task-generation number. The determination processing of simultaneous-task-generation number is to calculate, targeting each of the query blocks, the number of simultaneous task generation, which is the number of tasks simultaneously generatable as tasks for executing the query block. The number of the dynamically generated tasks is equal to or smaller than the number of simultaneous task generation.

Abstract: As an I/O method of issuing an I/O request, there are a synchronous I/O method, in which a task is in a waiting state until an I/O response to the I/O request is returned and an asynchronous I/O method, in which another task can be executed before an I/O response to the I/O request is returned. When issuing an I/O request in execution of a task, a DBMS selects any one of the synchronous I/O method and the asynchronous I/O method, based on an I/O response speed of an I/O destination storage device and issues an I/O request according to the selected I/O method.

Abstract: A database management system determines whether an exhibition performance, which is a performance exhibited by execution of a query being in execution, satisfies a predetermined condition continuously on and after a certain time point, based on an execution state of the database management system. When the determination result is affirmative and there is an execution-waiting query, the database management system starts execution of the execution-waiting query before execution of the query being in execution ends.

Abstract: There is a storage apparatus which provides a storage area, comprises a cache memory, reads data into the cache memory from the storage area according to a read request and sends the data from the cache memory, and a computer is coupled to the storage apparatus. The computer receives a data processing request, determines an access usage based on the data processing request (or, the information relating to an access usage of the data processing request), selects a logical device corresponding to the determined access usage from a plurality of logical devices which are allocated to the storage area and issues a read request to the selected logical device.

Abstract: Provided is a database management apparatus, having a processor, a memory, and a storage device, whereby a database which is stored in the storage device is managed, the database management apparatus further comprising: a query acceptance unit which accepts a query to the database; a query execution plan generating unit which generates a query execution plan which includes a database operation which is necessary for executing the accepted query; and a query execution unit which, in executing the accepted query on the basis of the generated query execution plan, dynamically generates a task for executing the database operation, and executes the dynamically generated task. The query execution unit acquires a resource usage state, and, when executing the next database operation, generates a new task on the basis of the resource usage state, and executes the new task in parallel with the task.

Abstract: According to this invention, a data arrangement method, the computer connected to a storage system which provides a plurality of logical storage devices comprising a plurality of physical storage devices arranges data in a logical storage volume constructed by integrating the plurality of logical storage devices. The method includes: a step wherein the computer receives an instruction to build the logical storage volume using the plurality of logical storage devices or to rebuild the constructed logical storage volume; a step wherein the computer obtains information about the plurality of physical storage devices constituting each of the plurality of logical storage devices included in the received instruction; and a step wherein the arrangement position of data into the logical storage volume is determined on the basis of the obtained information about the plurality of physical storage devices.

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 management system manages a plurality of data units constituting schemas of a database in a storage device, which includes a plurality of first storage device sets having a plurality of storage areas. An ordered schema constituted of the plurality of data units having order properties defining respective orders is included in the schemas. When a second storage device set, which is a set of one or more second storage devices and in which each of the storage areas is a free storage area, is added to the first storage device set, the management system migrates two or more data units not consecutive in the order among a plurality of data units stored in the plurality of storage areas in the first storage device set respectively from at least the one first storage device set to the free storage areas of the second storage device set.

Abstract: A database management system (DBMS) manages a database existing in a second storage device with an access speed lower than that of a first storage device. In an execution of a query, the DBMS dynamically generates tasks two or more executable tasks in parallel. The DBMS generates task start information which is information representing a content of the execution of the task, manages the task start information, and executes a content represented by the task start information by the task. The task start information includes a data address set existing in the second storage device. The DBMS controls movement of the data address sets between the first storage device and the second storage device based on a management state of the task start information. In addition, the DBMS selects the task start information based on whether or not the data address set exists in the first storage device.

Abstract: A database management system (DBMS) generates a query execution plan including information indicating one or more database (DB) operations necessary to execute the query. The DBMS dynamically generates a task for executing the DB operation in execution of the query. The DBMS performs a determination processing of simultaneous-task-generation number when newly creating a task. The determination processing of simultaneous-task-generation number is to calculate the number of simultaneous task generation, which is the number of tasks that can be generated simultaneously, based on the number of tasks which can be newly generated, a first memory resource amount which is the amount of memory resources necessary to be allocated per task newly generated, and a second memory resource amount which is the number of memory resources that can be newly allocated. The number of tasks generated dynamically and simultaneously is equal to or smaller than the calculated number of simultaneously generatable tasks.

Abstract: A database management system (DBMS) generates a query execution plan including information representing one or more database (DB) operations necessary for executing a query, and executes the query in accordance with the query execution plan. In the execution of the query, the DBMS dynamically generates tasks for executing the DB operations and executes the dynamically generated tasks. The query execution plan includes a plurality of query blocks, which are sets of one or more DB operations. When newly generating a task, the DBMS executes determination processing of simultaneous-task-generation number. The determination processing of simultaneous-task-generation number is to calculate, targeting each of the query blocks, the number of simultaneous task generation, which is the number of tasks simultaneously generatable as tasks for executing the query block. The number of the dynamically generated tasks is equal to or smaller than the number of simultaneous task generation.

Abstract: A parallel data processing system includes a parallel data processing execution unit for reading a data from a data set including a first data set that includes a plurality of first data and a second data set that includes a plurality of second data and executing processing. The parallel data processing execution unit (A) reads the first data from the first data set, and acquires a first value from the first data based on first format information acquired from an application, (B) generates one or more threads for respectively reading one or more second data corresponding to the first value from the second data set based on first reference information acquired from the application, (C) executes (A) and (B) on one or more first data in the first data set, and (D) executes a plurality of the threads in parallel.

Abstract: A database management system (DBMS) generates a query execution plan including information representing one or more database (DB) operations necessary for executing a query and executes the query based on the query execution plan. In the execution of the query, the DBMS dynamically generates a task for executing a DB operation and executes the dynamically generated task. The DBMS executes a task in a plurality of threads executed by a processor core.

Abstract: In a system manages a plurality of pieces of sensor information in a plant, or the like, it can be reducing an amount of data stored in a database and easily a processing for searching a place of an anomaly and an anomaly cause. A database management method for use in a computer for managing a database, the database management method including: a step of analyzing a query; a step of generating a first inquiry for searching the database for compressed data; a step of generating a second inquiry for executing a search of time-series data; a step of extracting given data from the obtained time-series data, based on a response result of the second inquiry; and a step of generating an output result by extracting data to be output to a client computer from the given data.

Abstract: A method for producing an ? alumina sintered body for the production of a sapphire single crystal characterized in that a relative density is 60% or more, a closed porosity is 10% or less, a purity is 99.99% by mass or more, each content of Si, Na, Ca, Fe, Cu and Mg is 10 ppm or less, and a volume is 1 cm3 or more, and the ? alumina sintered body can be obtained by mixing 100 parts by weight of an ? alumina with 1 part by weight or more and 20 parts by weight or less of an ? alumina precursor to obtain a mixture, forming a compact from the obtained mixture, and firing the obtained compact.

Abstract: The invention provides an application technique of a backup data in which a backup data can be utilized by creating a backup data including no indeterminate data in a backup system. In a backup system including a primary system and a backup system, the method of creating the backup data includes: a data update record rerun step for rerunning a data update record to a backup data; and a backup data creation step for starting a read to a backup data B, stopping a read to a backup data A, copying the backup data to the backup data A, starting the read to the backup data A, stopping the read to the backup data B, and copying the backup data A to the backup data B.

Abstract: A disaster recovery technology capable of achieving the high-speed FO and correctly reading the logs even if the unit of logs written in the main site is large is provided. In the disaster recovery system comprising a main site and a sub-site, when the writing in units of a log block consisting of a plurality of log records is performed in the main site and the logs are applied in the sub-site, the log blocks are read from the sub-storage to verify the consistency, and it is determined whether the reading process conflicts with the writing process through the remote copy operation when reading the logs. Then, only the log blocks in which the reading process does not conflict with the writing process as a result of the determination are applied to the database. Thereby, the logs are applied in the sub-site independently to recover the database.

Abstract: Provided is a database system in which sorting of query results is sped up. The database system stores storage location information in which storage locations of the pieces of data are recorded in a given order. When there is no second task, which is executed based on data that is fetched in a first task, whether every piece of data requested in a third task, which is executed before the first task, has been fetched is determined. In the case where every piece of data requested in the third task has been fetched, data fetched in the first task is output. In the case where some of the data requested in the third task has not been fetched, data fetched in the first task is kept in a temporary buffer until every piece of data requested in the third task is fetched, and then output.

Abstract: In executing query distributed processing in a computer system having a plurality of computers, a query and a sliding window are inherited between different computers. If a tuple having a new principal key value is detected when a query is to be executed, a relevant individual query and a relevant sliding window are inherited between computers, and further a sliding window of a relevant common query is inherited between computers.

Abstract: An object of the present invention is to provide ? alumina for the production of a sapphire single crystal, capable of producing a sapphire single crystal with high production efficiency; and a method for producing the same. Disclosed are ? alumina for the production of a sapphire single crystal, including 100 parts by weight of ? alumina (I) and 25 to 235 parts by weight of ? alumina (II), wherein the ? alumina (I) has a specific surface area of 0.1 to 5 m2/g and a bulk density of 1.5 g/cm3 or more, the ? alumina (II) is composed of sintered particles and also has a specific surface area of 1 m2/g or less and a relative density of 85% or more, and each of the body particles has a volume of 0.01 cm3 or more; and a method for producing the same.