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// file : hello/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 "person.hxx"
#include "person-odb.hxx"
using namespace std;
using namespace odb::core;
int
main (int argc, char* argv[])
{
try
{
auto_ptr<database> db (create_database (argc, argv));
unsigned long john_id, jane_id, joe_id;
// Create a few persistent person objects.
//
{
person john ("John", "Doe", 33);
person jane ("Jane", "Doe", 32);
person joe ("Joe", "Dirt", 30);
transaction t (db->begin ());
// Make objects persistent and save their ids for later use.
//
john_id = db->persist (john);
jane_id = db->persist (jane);
joe_id = db->persist (joe);
t.commit ();
}
typedef odb::query<person> query;
typedef odb::result<person> result;
// Say hello to those over 30.
//
{
transaction t (db->begin ());
result r (db->query<person> (query::age > 30));
for (result::iterator i (r.begin ()); i != r.end (); ++i)
{
cout << "Hello, " << i->first () << " " << i->last () << "!" << endl;
}
t.commit ();
}
// Joe Dirt just had a birthday, so update his age.
//
{
transaction t (db->begin ());
auto_ptr<person> joe (db->load<person> (joe_id));
joe->age (joe->age () + 1);
db->update (*joe);
t.commit ();
}
// Alternative implementation without using the id.
//
/*
{
transaction t (db->begin ());
result r (db->query<person> (query::first == "Joe" &&
query::last == "Dirt"));
result::iterator i (r.begin ());
if (i != r.end ())
{
auto_ptr<person> joe (i.load ());
joe->age (joe->age () + 1);
db->update (*joe);
}
t.commit ();
}
*/
// Print some statistics about all the people in our database.
//
{
transaction t (db->begin ());
odb::result<person_stat> r (db->query<person_stat> ());
// The result of this query always has exactly one element.
//
const person_stat& ps (*r.begin ());
cout << endl
<< "count : " << ps.count << endl
<< "min age: " << ps.min_age << endl
<< "max age: " << ps.max_age << endl;
t.commit ();
}
// John Doe is no longer in our database.
//
{
transaction t (db->begin ());
db->erase<person> (john_id);
t.commit ();
}
}
catch (const odb::exception& e)
{
cerr << e.what () << endl;
return 1;
}
}
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