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// file : query/driver.cxx
// copyright : not copyrighted - public domain
#include <vector>
#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 odb::database;
using odb::transaction;
typedef odb::query<person> query;
typedef odb::result<person> result;
static void
print (person& p)
{
cout << p.first () << " ";
if (!p.middle ().null ())
cout << p.middle ().get () << " ";
cout << p.last () << " " << p.age () << endl;
}
static void
print (result& r)
{
for (result::iterator i (r.begin ()); i != r.end (); ++i)
print (*i);
cout << endl;
}
int
main (int argc, char* argv[])
{
try
{
auto_ptr<database> db (create_database (argc, argv));
{
typedef vector<person> people;
people p;
p.push_back (person ("John", "Doe", 21));
p.push_back (person ("John", "Smith", 22));
p.push_back (person ("Jack", "Johnson", 31));
p.push_back (person ("John", "JJ", "Jackson", 32));
p.push_back (person ("Jane", "JD", "Doe", 23));
p.push_back (person ("Jane", "JS", "Smith", 24));
transaction t (db->begin ());
for (people::iterator i (p.begin ()); i != p.end (); ++i)
db->persist (*i);
t.commit ();
}
// A simple query and result handling.
//
{
transaction t (db->begin ());
result r (db->query<person> (query::age < 30));
for (result::iterator i (r.begin ()); i != r.end (); ++i)
{
cout << i->first () << " " << i->last () << " " << i->age () << endl;
}
// Alternatively we can get a dynamically-allocated object.
//
/*
for (result::iterator i (r.begin ()); i != r.end (); ++i)
{
auto_ptr<person> p (i.load ());
cout << p->first () << " " << p->last () << " " << p->age () << endl;
}
*/
// Or we can load the state into an existing object.
//
/*
person p ("", "", 0);
for (result::iterator i (r.begin ()); i != r.end (); ++i)
{
i.load (p);
cout << p.first () << " " << p.last () << " " << p.age () << endl;
}
*/
cout << endl;
t.commit ();
}
// Use query_one() as a shortcut when there's no more than one element
// in the result.
//
{
transaction t (db->begin ());
auto_ptr<person> p (db->query_one<person> (query::age == 21));
if (p.get () != 0)
{
print (*p);
cout << endl;
}
// Or we can load the state into an existing object.
//
/*
person p ("", "", 0);
if (db->query_one<person> (query::age == 21, p))
{
print (p);
cout << endl;
}
*/
t.commit ();
}
// Query that shows how to combine expressions with &&, ||, and !
// as well as use paranthesis to control evaluation order.
//
{
transaction t (db->begin ());
result r (
db->query<person> (
(query::first == "John" || query::first == "Jane") &&
!(query::last != "Doe" || query::age > 30)));
print (r);
t.commit ();
}
// Query that shows how to use by-reference parameter binding.
//
{
transaction t (db->begin ());
unsigned short lower, upper;
query q (query::age >= query::_ref (lower) &&
query::age < query::_ref (upper));
for (unsigned short band (0); band < 10; ++band)
{
lower = band * 10;
upper = lower + 10;
result r (db->query<person> (q));
if (!r.empty ())
{
cout << lower << '-' << (upper - 1) << ':' << endl;
print (r);
}
}
t.commit ();
}
// Query that shows how to use the in() function.
//
{
transaction t (db->begin ());
result r (
db->query<person> (
query::last.in ("Smith", "Johnson", "Jockson")));
print (r);
t.commit ();
}
// The same query but using the in_range() function.
//
{
vector<string> names;
names.push_back ("Smith");
names.push_back ("Johnson");
names.push_back ("Jockson");
transaction t (db->begin ());
result r (
db->query<person> (
query::last.in_range (names.begin (), names.end ())));
print (r);
t.commit ();
}
// Query that shows how to test for NULL values using the
// is_null()/is_not_null() functions.
//
{
transaction t (db->begin ());
result r (db->query<person> (query::middle.is_not_null ()));
print (r);
t.commit ();
}
}
catch (const odb::exception& e)
{
cerr << e.what () << endl;
return 1;
}
}
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