| 摘要 |
A relational database management system 10 has a runtime supervisor 22 and a data manager 30. Typically user application files do not conform to the definition of a base relation of the relational database management system. Therefore, for the use of the data manager a plurality of library procedures generalized for manipulation of user application files are provided installed with the database management system. Responsive to user selection, a class for user application files is defined by naming members of a set of the library procedures for use with member application files of the class and by naming the class. Further responsive to user selection, column definitions on an application file within the class are made to create a user defined table 28. The user defined table corresponds to a specified user application file and to the definition. A class control block 26 is created in which the members of the set of library procedures are named for the class and a user defined table control block 28 is created in which the column definitions are stored. Both control blocks are accessible to the runtime supervisor for use with an access plan generated from SQL statements. Special structured query language statements are provided for user invocation to define a class of user application files and for providing column definitions, as well as for deleting a class control block and a user defined table control block. <IMAGE> |
