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Diffstat (limited to 'query/driver.cxx')
-rw-r--r-- | query/driver.cxx | 183 |
1 files changed, 183 insertions, 0 deletions
diff --git a/query/driver.cxx b/query/driver.cxx new file mode 100644 index 0000000..15f6129 --- /dev/null +++ b/query/driver.cxx @@ -0,0 +1,183 @@ +// file : query/driver.cxx +// author : Boris Kolpackov <boris@codesynthesis.com> +// 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 (result& r) +{ + for (result::iterator i (r.begin ()); i != r.end (); ++i) + { + cout << i->first () << " " << i->last () << " " << i->age () << endl; + } + + 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", "Jackson", 32)); + p.push_back (person ("Jane", "Doe", 23)); + p.push_back (person ("Jane", "Smith", 24)); + + transaction t (db->begin_transaction ()); + + 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_transaction ()); + + 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 (); + } + + // Query that shows how to combine expressions with &&, ||, and ! + // as well as use paranthesis to control evaluation order. + // + { + transaction t (db->begin_transaction ()); + + 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_transaction ()); + + 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_transaction ()); + + 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_transaction ()); + + result r ( + db->query<person> ( + query::last.in_range (names.begin (), names.end ()))); + + print (r); + + t.commit (); + } + } + catch (const odb::exception& e) + { + cerr << e.what () << endl; + return 1; + } +} |