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diff --git a/composite/README b/composite/README new file mode 100644 index 0000000..fc508bb --- /dev/null +++ b/composite/README @@ -0,0 +1,56 @@ +This example shows how to use composite value types as data members in objects +and other value types, as element types in containers, and as base types for +other composite value types. It also shows how to use composite value type +data members in queries. + +The example consists of the following files: + +person.hxx + Header file defining the 'basic_name', 'name_extras', and 'name' composite + value types. It also defines the 'person' persistent class which use the + 'name' value type in one of its data members. + +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-schema --generate-query 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 'person' class and the database support + code for this class. It also includes database.hxx for the + create_database() function declaration. + + In main() the driver first calls create_database() to obtain the database + instance. It then persists a 'person' object, loads it and updates its + nickname and aliases which reside in a composite value type, then re-loads + the object and prints its name to verify that the changes have been made + persistent. Finally, the driver performs a database query which uses a + data member from the composite value type in its criterion. + +To run the example we first need to create the database schema. 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 |