From ab51fa65f9e8cad4ef5a1db85029dfe6404e9a1f Mon Sep 17 00:00:00 2001 From: Boris Kolpackov Date: Thu, 13 Jan 2011 11:31:14 +0200 Subject: Add composite, relationship, and inverse examples All add the TR1 test for the latter two examples. --- inverse/README | 67 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 67 insertions(+) create mode 100644 inverse/README (limited to 'inverse/README') diff --git a/inverse/README b/inverse/README new file mode 100644 index 0000000..2c89c62 --- /dev/null +++ b/inverse/README @@ -0,0 +1,67 @@ +This example shows how to declare and use bidirectional one-to-one, one-to- +many, and many-to-many relationships between persistent objects. It also +shows how to work with lazy pointers. All the relationships presented in +this example declare one side as inverse in order to produce canonical +database schema. + +The example uses the shared_ptr and weak_ptr smart pointers from TR1 and +requires a C++ compiler with TR1 support or an external TR1 implementation, +such as the one provided by Boost. + +The example consists of the following files: + +employee.hxx + Header file defining the 'employee', 'employer', 'position', and 'project' + persistent classes as well as the employer-employee (one-to-many), + employee-position (one-to-one), and employee-project (many-to-many) + bidirectional relationships between them. + +employee-odb.hxx +employee-odb.ixx +employee-odb.cxx +employee.sql + The first three files contain the database support code and the last file + contains the database schema for the employee.hxx header. + + These files are generated by the ODB compiler from employee.hxx using the + following command line: + + odb -d --generate-schema --generate-query \ + --default-pointer std::tr1::shared_ptr employee.hxx + + Where stands for the database system we are using, for example, + 'mysql'. + + The --default-pointer option is used to make TR1 shared_ptr the default + object pointer. + +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 employee.hxx and employee-odb.hxx + headers to gain access to the 'employee' 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 creates a number of 'employee', 'employer', 'position', + and 'project' objects, sets the relationships between them, and persists + them in the database. In the next few transactions the driver loads various + objects, then accesses and modifies the relationships between them. Finally, + the driver performs a database query which uses a data member from a related + object 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 < employee.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 -- cgit v1.1