1 files changed, 168 insertions, 0 deletions
diff --git a/relationship/driver.cxx b/relationship/driver.cxx
new file mode 100644
index 0000000..9d09913
--- /dev/null
+++ b/relationship/driver.cxx
@@ -0,0 +1,168 @@
+// file      : relationship/driver.cxx
+// author    : Boris Kolpackov <boris@codesynthesis.com>
+// copyright : not copyrighted - public domain
+
+#include <memory>   // std::auto_ptr
+#include <iostream>
+
+#include <odb/database.hxx>
+#include <odb/transaction.hxx>
+
+#include "database.hxx" // create_database
+
+#include "employee.hxx"
+#include "employee-odb.hxx"
+
+using namespace std;
+using namespace odb;
+
+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
+  {
+    auto_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"));
+
+      result r (db->query<employee> (query::first == "John" &&
+                                     query::last == "Doe"));
+
+      shared_ptr<employee> john (r.begin ().load ());
+
+      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;
+  }
+}