Database processing method and apparatus, and medium for recording processing program thereof

A database system, including a front-end server, that is a logical unit of a database management system, for accepting a query from a user and analyzing the query and at least one back-end server, that is a logical unit of a database management system, for accessing data in a database, the front-end server and the back-end server being on different computers, for invoking a module to implement a user-defined function related to a data type in a query, and conducting processing, said database system comprising:

• a module definition information registration unit for storing information whether a module for implementing the user-defined function accesses a specific database resource which is necessary data to estimate the user-defined function and which is not table data;
• a module execution procedure determination processing unit for analyzing a query given by a user, and
• if the user-defined function accesses specific database resource which is necessary to estimate the user-defined function and which is not table data, determining an execution procedure so as to invoke the module in the back-end server having the specific database resource, if the user-defined function does not access said specific database resource which is necessary data to estimate the user-defined function and which is not table data, determining an execution procedure so as to invoke the module in the front-end server.

A medium for recording a program, said program causing a computer to function as a database system, including a front-end server module for accepting a query from a user and analyzing the query and at least one back-end server module for accessing data in a database, the front-end server module and the back-end server module being different modules, for invoking a module to implement a user-defined function related to a data type in a query, and conducting processing, said medium recording a program to cause a computer to function as:

• a module definition information registration unit for storing information whether a module for implementing the user-defined function accesses a specific database resource which is necessary data to estimate the user-defined function and which is not table data;
• a module execution procedure determination processing unit for analyzing a query given by a user, and
• if the user-defined function accesses a specific database resource which is necessary data to estimate the user-defined function and which is not table data, determining an execution procedure so as to invoke the module in the back-end server having said specific database resource which is necessary data to estimate the user-defined function and which is not table data, if the user-defined function does not access said specific database resource which is necessary data to estimate the user-defined function and which is not table data, determining an execution procedure so as to invoke the module in the front-end server.

A program for causing a computer to function as a database system, including a front-end server module for accepting a query from a user and analyzing the query and at least one back-end server module for accessing data in a database, the front-end server module and the back-end server module being different modules, for invoking a module to implement a user-defined function related to a data type in a query, and conducting processing, said program comprising:

• a module definition information registration unit for storing information whether a module for implementing the user-defined function accesses a specific database resource which is necessary data to estimate the user-defined function and which is not table data;
• a module execution procedure determination processing unit for analyzing a query given by a user, and determining an execution timing and an execution procedure so as to invoke said module in a database system storing and managing said specific database resource which is necessary data to estimate the user-defined function and which is not table data, if said information indicates that the module accesses said specific database resource which is necessary data to estimate the user-defined function and which is not table data;
• and
• a processing unit for, if the user-defined function accesses said specific database resource, determining an execution procedure so as to invoke the module in the back-end server having said specific database resource which is necessary data to estimate the user-defined function and which is not table data, if the user-defined function does not access a specific database resource which is not necessary to estimate the user-defined function and which is not table data, determining an execution procedure so as to invoke the module in the front-end server.

A user-defined function implementing method in a database system including front-end servers, that are logical units of a database management system and back-end servers, that are logical units of a database management system, each back-end server having a database resource, comprising the steps of:

• registering a module for implementing a user-defined function with information on whether the user-defined function accesses said specific database resource which is necessary data to estimate the user-defined function and which is not table data, each specific database resource being part of a partitioned database and belonging to a specific back-end server;
• accepting a query from a user;
• checking if the query includes the user-defined function;
• checking the registered information of the module for implementing the user-defined function included in the query, if the user-defined function existed in the query;
• and
• if the user-defined function accesses said specific database resource which is necessary data to estimate the user-defined function and which is not table data, determining an execution procedure so as to invoke the module in the back-end server having said specific database resource which is necessary data to estimate the user-defined function and which is not table data, if the user-defined function does not access a specific database resource, determining an execution procedure so as to invoke the module in the front-end server.

A database system comprising:

• front-end servers, that are logical units of a database management system;
• and
• back-end servers, that are logical units of a database management system, each back-end server having a database resource, each database resource being part of a partitioned database,
• wherein the front-end server includes:
• means for registering a module for implementing a user-defined function with information on whether the user-defined function accesses a specific database resource which is necessary data to estimate the user-defined function and which is not table data;
• means for accepting a query from a user;
• means for checking if the query includes the user-defined function;
• means for checking the registered information of the module for implementing the user-defined function included in the query, if the user-defined function existed in the query;
• and
• means for, if the user-defined function accesses said specific database resource which is necessary data to estimate the user-defined function and which is not table data, determining an execution procedure so as to invoke the module in the back-end server having said specific database resource which is necessary data to estimate the user-defined function and which is not table data, if the user-defined function does not access said specific database resource which is necessary data to estimate the user-defined function and which is not table data, determining an execution procedure so as to invoke the module in the front-end server.