Distributed data retrieval system including mechanism for predicting an amount of response data
AssigneeFujitsu Limited
InventorNaohito Nakamura
Life of this patent
Estimating the term…
Abstract
When a predetermined number of pieces of data are retrieved, a retrieving process is performed first on a local database 7 in a LAN 1, and a response counter 8 counts the number of pieces of response data accumulated in a response accumulation device 9. When it is determined that the predetermined number of pieces of response data cannot be obtained from the local database, a remote database 3 is searched by a retrieval device 6 through a communications device 2. Therefore, requests to search unnecessary databases can be reduced, and the load on a network and the remote database 3 can also be reduced successfully.
Claims9
A data access apparatus functioning as a distributed retrieval system in which a plurality of databases are distributed in a network, and retrieving response data satisfying a predetermined condition based on a specific database, comprising:
- a retrieval unit retrieving over the network from the specific database, and obtaining data satisfying the predetermined condition as a response;
- a count unit generating count information by counting a number of pieces of response data as they are being obtained over the network by said retrieval unit searching the specific database;
- a prediction unit predicting a likely number of pieces of response data to be finally obtained over the network as a result of said retrieval unit searching the specific database according to the count information from said count unit and information about the amount of data stored in the specific database;
- and
- said retrieval unit requesting over the network to search another database in the network when a number of pieces of prediction responses obtained by said prediction unit does not reach a predetermined value, where the search of the other database occurs while the data from the specific database is being obtained.
A data access apparatus functioning as a distributed retrieval system in which a plurality of databases are distributed in a network, and retrieving response data satisfying a predetermined condition based on a specific database, comprising:
- a retrieval unit retrieving over the network from the specific database and obtaining data satisfying the predetermined condition as a response, requesting no more than a particular number of pieces of appropriately retrieved response data from each of other databases in the network when a retrieval request message is issued over the network to the other databases, and receiving over the network response data from the other databases obtained as a result of searching each of the other databases responsive to the request message issued from said retrieval unit;
- and
- a prediction unit predicting a number of pieces of response data likely to be obtained from each of the other databases, wherein
- said retrieval unit determines the particular number of pieces of response data requested over the network from each of the other databases using a prediction result of said prediction unit.
A data accessing method functioning as a distributed retrieval system in which a plurality of databases are distributed in a network, and retrieving response data satisfying a predetermined condition based on a specific database, comprising:
- retrieving to a search system from the specific database, and obtaining over the network data satisfying the predetermined condition as a response;
- counting a number of pieces of response data obtained by said retrieving the specific database;
- predicting at the search system a number of pieces of response data to be finally obtained as a result of said retrieving according to count information from said counting and according to information about an amount of data stored in the specific database;
- and
- retrieval-requesting over the network to search another database in the network when a number of pieces of prediction responses obtained in said predicting does not reach a predetermined value.
A computer-readable storage medium, in a system functioning as a distributed retrieval system in which a plurality of databases are distributed in a network, and retrieving response data satisfying a predetermined condition based on a specific database, storing a program used to direct a computer to perform the functions of:
- retrieving to a search system from the specific database, and obtaining over the network data satisfying the predetermined condition as a response to a message sent by the search system;
- counting at the search system a number of pieces of response data obtained by said retrieving function searching the specific database;
- predicting at the search system a number of pieces of response data to be finally obtained as a result of said retrieving function according to count information from said counting function and according to information about an amount of data stored in the specific database;
- and
- retrieval-requesting to search another database in the network when a number of pieces of prediction responses obtained in said predicting function does not reach a predetermined value by the search system sending a retrieval request message over the network to the other database.
Dependencies are inferred from the claim text.