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GNU Info (slib.info)Creating and Opening Relational DatabasesCreating and Opening Relational Databases ----------------------------------------- - Function: make-relational-system base-table-implementation Returns a procedure implementing a relational database using the BASE-TABLE-IMPLEMENTATION. All of the operations of a base table implementation are accessed through a procedure defined by `require'ing that implementation. Similarly, all of the operations of the relational database implementation are accessed through the procedure returned by `make-relational-system'. For instance, a new relational database could be created from the procedure returned by `make-relational-system' by: (require 'alist-table) (define relational-alist-system (make-relational-system alist-table)) (define create-alist-database (relational-alist-system 'create-database)) (define my-database (create-alist-database "mydata.db")) What follows are the descriptions of the methods available from relational system returned by a call to `make-relational-system'. - Function: create-database filename Returns an open, nearly empty relational database associated with FILENAME. The only tables defined are the system catalog and domain table. Calling the `close-database' method on this database and possibly other operations will cause FILENAME to be written to. If FILENAME is `#f' a temporary, non-disk based database will be created if such can be supported by the underlying base table implelentation. If the database cannot be created as specified `#f' is returned. For the fields and layout of descriptor tables, Note: Catalog Representation - Function: open-database filename mutable? Returns an open relational database associated with FILENAME. If MUTABLE? is `#t', this database will have methods capable of effecting change to the database. If MUTABLE? is `#f', only methods for inquiring the database will be available. Calling the `close-database' (and possibly other) method on a MUTABLE? database will cause FILENAME to be written to. If the database cannot be opened as specified `#f' is returned. automatically generated by info2www version 1.2.2.9 |