diff options
Diffstat (limited to 'odb-examples/relationship')
| -rw-r--r-- | odb-examples/relationship/README | 70 | ||||
| -rw-r--r-- | odb-examples/relationship/buildfile | 47 | ||||
| -rw-r--r-- | odb-examples/relationship/database.hxx | 95 | ||||
| -rw-r--r-- | odb-examples/relationship/driver.cxx | 167 | ||||
| -rw-r--r-- | odb-examples/relationship/employee.hxx | 154 | ||||
| -rw-r--r-- | odb-examples/relationship/testscript | 13 |
6 files changed, 546 insertions, 0 deletions
diff --git a/odb-examples/relationship/README b/odb-examples/relationship/README new file mode 100644 index 0000000..fd4e3cd --- /dev/null +++ b/odb-examples/relationship/README @@ -0,0 +1,70 @@ +This example shows how to declare and use unidirectional to-one and to-many +relationships between persistent objects. + +The example consists of the following files: + +employee.hxx + Header file defining the 'employee', 'employer', and 'project' persistent + classes as well as the employee-employer (to-one) and employee-project (to- + many) unidirectional 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 --std c++11 -d <database> --generate-schema --generate-query \ + --generate-session --default-pointer std::shared_ptr employee.hxx + + Where <database> stands for the database system we are using, for example, + 'pgsql'. + + The --generate-session option is used to enable session support for all + the persistent classes in employee.hxx. The --default-pointer option is + used to make std::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 persistent classes and their 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. It then creates a number of 'employee', 'employer', 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 compile and link the example manually from the command line we can use the +following commands (using PostgreSQL as an example; replace 'c++' with your +C++ compiler name): + +c++ -c employee-odb.cxx +c++ -DDATABASE_PGSQL -c driver.cxx +c++ -o driver driver.o employee-odb.o -lodb-pgsql -lodb + +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 PostgreSQL as an example, this +can be achieved with the following command: + +psql --username=odb_test --dbname=odb_test -f 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 PostgreSQL as +the database): + +./driver --user odb_test --database odb_test diff --git a/odb-examples/relationship/buildfile b/odb-examples/relationship/buildfile new file mode 100644 index 0000000..2b4ffed --- /dev/null +++ b/odb-examples/relationship/buildfile @@ -0,0 +1,47 @@ +# file : relationship/buildfile +# license : GNU GPL v2; see accompanying LICENSE file + +import libodb = libodb%lib{odb} + +import libs = libodb-$database%lib{odb-$database} + +exe{driver}: {hxx cxx}{* -employee-odb} {hxx ixx cxx}{employee-odb} testscript + +# The metadata library target which we use to extract the poptions variable +# value for specifying the preprocessor options (-I, etc) on the ODB compiler +# command line. +# +libue{employee-meta}: $libodb + +exe{driver}: libue{employee-meta} $libs + +<{hxx ixx cxx}{employee-odb}>: hxx{employee} libue{employee-meta} $odb +{{ + pops = $cxx.lib_poptions($<[1]) + depdb hash $pops + + depdb dyndep --dyn-target --target-what 'generated schema' --format lines \ + -- echo ($sqlite ? '' : "$out_base/employee.sql") + + $odb --std c++11 \ + --database $database \ + --generate-schema \ + --generate-query \ + --generate-session \ + --default-pointer std::shared_ptr \ + --output-dir $out_base \ + --table-prefix relation_ \ + "-I$src_base" $pops \ + $path($<[0]) +}} + +cxx.poptions =+ "-I$out_base" "-I$src_base" -DDATABASE_$ucase($database) + +# Testscript's run-time prerequisites. +# +# @@ BUILD2: Eventually we should be able to mark it as test.input once +# this is supported for testscript tests. +# +exe{driver}: ../alias{database-client}: include = adhoc + +testscript@./: schema = employee diff --git a/odb-examples/relationship/database.hxx b/odb-examples/relationship/database.hxx new file mode 100644 index 0000000..17d8393 --- /dev/null +++ b/odb-examples/relationship/database.hxx @@ -0,0 +1,95 @@ +// file : relationship/database.hxx +// copyright : not copyrighted - public domain + +// +// Create concrete database instance based on the DATABASE_* macros. +// + +#ifndef DATABASE_HXX +#define DATABASE_HXX + +#include <string> +#include <memory> // std::unique_ptr +#include <cstdlib> // std::exit +#include <iostream> + +#include <odb/database.hxx> + +#if defined(DATABASE_MYSQL) +# include <odb/mysql/database.hxx> +#elif defined(DATABASE_SQLITE) +# include <odb/connection.hxx> +# include <odb/transaction.hxx> +# include <odb/schema-catalog.hxx> +# include <odb/sqlite/database.hxx> +#elif defined(DATABASE_PGSQL) +# include <odb/pgsql/database.hxx> +#elif defined(DATABASE_ORACLE) +# include <odb/oracle/database.hxx> +#elif defined(DATABASE_MSSQL) +# include <odb/mssql/database.hxx> +#else +# error unknown database; did you forget to define the DATABASE_* macros? +#endif + +inline std::unique_ptr<odb::database> +create_database (int& argc, char* argv[]) +{ + using namespace std; + using namespace odb::core; + + if (argc > 1 && argv[1] == string ("--help")) + { + cout << "Usage: " << argv[0] << " [options]" << endl + << "Options:" << endl; + +#if defined(DATABASE_MYSQL) + odb::mysql::database::print_usage (cout); +#elif defined(DATABASE_SQLITE) + odb::sqlite::database::print_usage (cout); +#elif defined(DATABASE_PGSQL) + odb::pgsql::database::print_usage (cout); +#elif defined(DATABASE_ORACLE) + odb::oracle::database::print_usage (cout); +#elif defined(DATABASE_MSSQL) + odb::mssql::database::print_usage (cout); +#endif + + exit (0); + } + +#if defined(DATABASE_MYSQL) + unique_ptr<database> db (new odb::mysql::database (argc, argv)); +#elif defined(DATABASE_SQLITE) + unique_ptr<database> db ( + new odb::sqlite::database ( + argc, argv, false, SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE)); + + // Create the database schema. Due to bugs in SQLite foreign key + // support for DDL statements, we need to temporarily disable + // foreign keys. + // + { + connection_ptr c (db->connection ()); + + c->execute ("PRAGMA foreign_keys=OFF"); + + transaction t (c->begin ()); + schema_catalog::create_schema (*db); + t.commit (); + + c->execute ("PRAGMA foreign_keys=ON"); + } +#elif defined(DATABASE_PGSQL) + unique_ptr<database> db (new odb::pgsql::database (argc, argv)); +#elif defined(DATABASE_ORACLE) + unique_ptr<database> db (new odb::oracle::database (argc, argv)); +#elif defined(DATABASE_MSSQL) + unique_ptr<database> db ( + new odb::mssql::database (argc, argv, false, "TrustServerCertificate=yes")); +#endif + + return db; +} + +#endif // DATABASE_HXX diff --git a/odb-examples/relationship/driver.cxx b/odb-examples/relationship/driver.cxx new file mode 100644 index 0000000..1f74824 --- /dev/null +++ b/odb-examples/relationship/driver.cxx @@ -0,0 +1,167 @@ +// file : relationship/driver.cxx +// copyright : not copyrighted - public domain + +#include <memory> // std::unique_ptr, std::shared_ptr +#include <iostream> + +#include <odb/database.hxx> +#include <odb/session.hxx> +#include <odb/transaction.hxx> + +#include "database.hxx" // create_database + +#include "employee.hxx" +#include "employee-odb.hxx" + +using namespace std; +using namespace odb::core; + +void +print (const employee& e) +{ + cout << e.first () << " " << e.last () << endl + << " employer: " << e.employer ()->name () << endl; + + const projects& ps (e.projects ()); + + for (projects::const_iterator i (ps.begin ()); i != ps.end (); ++i) + { + shared_ptr<project> p (*i); + cout << " project: " << p->name () << endl; + } + + cout << endl; +} + +int +main (int argc, char* argv[]) +{ + try + { + unique_ptr<database> db (create_database (argc, argv)); + + // Create a few persistent objects. + // + { + // Simple Tech Ltd. + // + { + shared_ptr<employer> er (new employer ("Simple Tech Ltd")); + + shared_ptr<project> sh (new project ("Simple Hardware")); + shared_ptr<project> ss (new project ("Simple Software")); + + shared_ptr<employee> john (new employee ("John", "Doe", er)); + shared_ptr<employee> jane (new employee ("Jane", "Doe", er)); + + john->projects ().push_back (sh); + john->projects ().push_back (ss); + jane->projects ().push_back (ss); + + transaction t (db->begin ()); + + db->persist (er); + + db->persist (sh); + db->persist (ss); + + db->persist (john); + db->persist (jane); + + t.commit (); + } + + // Complex Systems Inc. + // + { + shared_ptr<employer> er (new employer ("Complex Systems Inc")); + + shared_ptr<project> ch (new project ("Complex Hardware")); + shared_ptr<project> cs (new project ("Complex Software")); + + shared_ptr<employee> john (new employee ("John", "Smith", er)); + shared_ptr<employee> jane (new employee ("Jane", "Smith", er)); + + john->projects ().push_back (cs); + jane->projects ().push_back (ch); + jane->projects ().push_back (cs); + + transaction t (db->begin ()); + + db->persist (er); + + db->persist (ch); + db->persist (cs); + + db->persist (john); + db->persist (jane); + + t.commit (); + } + } + + typedef odb::query<employee> query; + typedef odb::result<employee> result; + + // Load employees with "Doe" as the last name and print what we've got. + // We use a session in this and subsequent transactions to make sure + // that a single instance of any particular object (e.g., employer) is + // shared among all objects (e.g., employee) that relate to it. + // + { + session s; + transaction t (db->begin ()); + + result r (db->query<employee> (query::last == "Doe")); + + for (result::iterator i (r.begin ()); i != r.end (); ++i) + print (*i); + + t.commit (); + } + + // John Doe has moved to Complex Systems Inc and is now working on + // Complex Hardware. + // + { + session s; + transaction t (db->begin ()); + + shared_ptr<employer> csi (db->load<employer> ("Complex Systems Inc")); + shared_ptr<project> ch (db->load<project> ("Complex Hardware")); + + shared_ptr<employee> john ( + db->query_one<employee> (query::first == "John" && + query::last == "Doe")); + + john->employer (csi); + john->projects ().clear (); + john->projects ().push_back (ch); + + db->update (john); + + t.commit (); + } + + // We can also use members of the pointed-to objects in the queries. The + // following transaction prints all the employees of Complex Systems Inc. + // + { + session s; + transaction t (db->begin ()); + + result r (db->query<employee> ( + query::employer->name == "Complex Systems Inc")); + + for (result::iterator i (r.begin ()); i != r.end (); ++i) + print (*i); + + t.commit (); + } + } + catch (const odb::exception& e) + { + cerr << e.what () << endl; + return 1; + } +} diff --git a/odb-examples/relationship/employee.hxx b/odb-examples/relationship/employee.hxx new file mode 100644 index 0000000..4133c05 --- /dev/null +++ b/odb-examples/relationship/employee.hxx @@ -0,0 +1,154 @@ +// file : relationship/employee.hxx +// copyright : not copyrighted - public domain + +#ifndef EMPLOYEE_HXX +#define EMPLOYEE_HXX + +#include <vector> +#include <string> +#include <memory> // std::shared_ptr + +#include <odb/core.hxx> + +// The "pointer architecture" in this object model is as follows: All +// object pointers are eager. The employee class holds shared pointers +// to employer and projects. +// +// The following unidirectional relationships are used: +// +// to-one : employee -> employer +// to-many : employee -> project +// + +// Forward declarations. +// +class employer; +class project; +class employee; + +typedef std::vector<std::shared_ptr<project>> projects; + +#pragma db object +class employer +{ +public: + employer (const std::string& name) + : name_ (name) + { + } + + const std::string& + name () const + { + return name_; + } + +private: + friend class odb::access; + + employer () {} + + #pragma db id + std::string name_; +}; + +#pragma db object +class project +{ +public: + project (const std::string& name) + : name_ (name) + { + } + + const std::string& + name () const + { + return name_; + } + +private: + friend class odb::access; + + project () {} + + #pragma db id + std::string name_; +}; + +#pragma db object +class employee +{ +public: + typedef ::employer employer_type; + + employee (const std::string& first, + const std::string& last, + std::shared_ptr<employer_type> employer) + : first_ (first), last_ (last), employer_ (employer) + { + } + + // Name. + // + const std::string& + first () const + { + return first_; + } + + const std::string& + last () const + { + return last_; + } + + // Employer. + // + std::shared_ptr<employer_type> + employer () const + { + return employer_; + } + + void + employer (std::shared_ptr<employer_type> employer) + { + employer_ = employer; + } + + // Projects. + // + typedef ::projects projects_type; + + const projects_type& + projects () const + { + return projects_; + } + + projects_type& + projects () + { + return projects_; + } + +private: + friend class odb::access; + + employee () {} + + #pragma db id auto + unsigned long id_; + + std::string first_; + std::string last_; + + #pragma db not_null + std::shared_ptr<employer_type> employer_; + + #pragma db value_not_null unordered + projects_type projects_; +}; + +#endif // EMPLOYEE_HXX diff --git a/odb-examples/relationship/testscript b/odb-examples/relationship/testscript new file mode 100644 index 0000000..d23eb2d --- /dev/null +++ b/odb-examples/relationship/testscript @@ -0,0 +1,13 @@ +# file : relationship/testscript +# license : GNU GPL v2; see accompanying LICENSE file + +.include ../database-options.testscript +.include ../$(database).testscript + ++if! $sqlite + $create_schema +end + +: basics +: +$* >| |