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diff --git a/access/README b/access/README new file mode 100644 index 0000000..ebf27db --- /dev/null +++ b/access/README @@ -0,0 +1,55 @@ +This example shows various approaches used by ODB to access data members +that cannot be accessed directly. Approaches that are illustrated by this +example include the automatic discovery of suitable accessor/modifier +functions, explicit specification of the accessor/modifier functions, +explicit specification of more complex accessor/modifier expressions, and +use of virtual data members. + +The example consists of the following files: + +person.hxx + Header file implementing the 'person' persistent class. + +person-odb.hxx +person-odb.ixx +person-odb.cxx +person.sql + The first three files contain the database support code and the last file + contains the database schema for the person.hxx header. + + These files are generated by the ODB compiler from person.hxx using the + following command line: + + odb -d <database> --generate-query --generate-schema person.hxx + + Where <database> stands for the database system we are using, for example, + 'mysql'. + +database.hxx + Contains the create_database() function which instantiates the concrete + database class corresponding to the database system we are using. + +driver.cxx + Driver for the example. It includes the person.hxx and person-odb.hxx + headers to gain access to the persistent class and its database support + code. It also includes database.hxx for the create_database() function + declaration. + + In main() the driver first calls create_database() to obtain the database + instance. Then it executes a number of database transactions on the 'person' + objects. + +To run the example we may first need to create the database schema (for some +database systems, such as SQLite, the schema is embedded into the generated +code which makes this step unnecessary). Using MySQL as an example, this +can be achieved with the following command: + +mysql --user=odb_test --database=odb_test < person.sql + +Here we use 'odb_test' as the database login and also 'odb_test' as the +database name. + +Once the database schema is ready, we can run the example (using MySQL as +the database): + +./driver --user odb_test --database odb_test |