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// file : schema/custom/driver.cxx
// copyright : not copyrighted - public domain
#include <memory> // std::auto_ptr
#include <iostream>
#include <odb/database.hxx>
#include <odb/connection.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;
int
main (int argc, char* argv[])
{
try
{
auto_ptr<database> db (create_database (argc, argv));
// Create the database schema.
//
#if defined(DATABASE_MYSQL) || \
defined(DATABASE_SQLITE) || \
defined(DATABASE_MSSQL)
{
// Due to bugs in SQLite foreign key support for DDL statements,
// we need to temporarily disable foreign keys.
//
connection_ptr c (db->connection ());
#ifdef DATABASE_SQLITE
c->execute ("PRAGMA foreign_keys=OFF");
#endif
transaction t (c->begin ());
// Try to drop the tables if they exist and ignore the error
// if they don't.
//
try
{
db->execute ("DROP TABLE EmployeeDegree");
db->execute ("DROP TABLE Employee");
db->execute ("DROP TABLE Employer");
}
catch (const odb::exception&)
{
}
db->execute (
"CREATE TABLE Employer ("
"name VARCHAR (255) NOT NULL PRIMARY KEY)");
db->execute (
"CREATE TABLE Employee ("
"ssn INTEGER NOT NULL PRIMARY KEY,"
"first_name VARCHAR (255) NOT NULL,"
"last_name VARCHAR (255) NOT NULL,"
"employer VARCHAR (255) NOT NULL REFERENCES Employer (name))");
db->execute (
"CREATE TABLE EmployeeDegree ("
"ssn INTEGER NOT NULL REFERENCES Employee (ssn),"
"degree VARCHAR (255) NOT NULL)");
t.commit ();
#ifdef DATABASE_SQLITE
c->execute ("PRAGMA foreign_keys=ON");
#endif
}
#elif defined(DATABASE_PGSQL)
{
// PostgreSQL-specific SQL.
//
transaction t (db->begin ());
db->execute ("DROP TABLE IF EXISTS \"Employer\" CASCADE");
db->execute ("DROP TABLE IF EXISTS \"Employee\" CASCADE");
db->execute ("DROP TABLE IF EXISTS \"EmployeeDegree\" CASCADE");
db->execute (
"CREATE TABLE \"Employer\" ("
"name VARCHAR (255) NOT NULL PRIMARY KEY)");
db->execute (
"CREATE TABLE \"Employee\" ("
"ssn INTEGER NOT NULL PRIMARY KEY,"
"first_name VARCHAR (255) NOT NULL,"
"last_name VARCHAR (255) NOT NULL,"
"employer VARCHAR (255) NOT NULL)");
db->execute (
"CREATE TABLE \"EmployeeDegree\" ("
"ssn INTEGER NOT NULL,"
"degree VARCHAR (255) NOT NULL)");
db->execute (
"ALTER TABLE \"Employee\" "
"ADD FOREIGN KEY (employer) "
"REFERENCES \"Employer\" "
"INITIALLY DEFERRED");
db->execute (
"ALTER TABLE \"EmployeeDegree\" "
"ADD FOREIGN KEY (ssn) "
"REFERENCES \"Employee\" "
"INITIALLY DEFERRED");
t.commit ();
}
#elif defined(DATABASE_ORACLE)
{
// Oracle-specific PL/SQL.
//
transaction t (db->begin ());
db->execute ("BEGIN "
" EXECUTE IMMEDIATE "
" 'DROP TABLE \"Employer\" CASCADE CONSTRAINTS';"
" EXCEPTION "
" WHEN OTHERS THEN "
" IF SQLCODE != -942 THEN RAISE; END IF;"
"END;");
db->execute ("BEGIN "
" EXECUTE IMMEDIATE "
" 'DROP TABLE \"Employee\" CASCADE CONSTRAINTS';"
" EXCEPTION "
" WHEN OTHERS THEN "
" IF SQLCODE != -942 THEN RAISE; END IF;"
"END;");
db->execute ("BEGIN "
" EXECUTE IMMEDIATE 'DROP TABLE \"EmployeeDegree\"';"
" EXCEPTION "
" WHEN OTHERS THEN "
" IF SQLCODE != -942 THEN RAISE; END IF;"
"END;");
db->execute (
"CREATE TABLE \"Employer\" ("
"\"name\" VARCHAR (255) PRIMARY KEY)");
db->execute (
"CREATE TABLE \"Employee\" ("
"\"ssn\" NUMBER(10) PRIMARY KEY,"
"\"first_name\" VARCHAR (255) NOT NULL,"
"\"last_name\" VARCHAR (255) NOT NULL,"
"\"employer\" VARCHAR (255) NOT NULL)");
db->execute (
"CREATE TABLE \"EmployeeDegree\" ("
"\"ssn\" NUMBER(10) NOT NULL,"
"\"degree\" VARCHAR (255) NOT NULL)");
db->execute (
"ALTER TABLE \"Employee\" "
"ADD FOREIGN KEY (\"employer\") "
"REFERENCES \"Employer\" "
"INITIALLY DEFERRED");
db->execute (
"ALTER TABLE \"EmployeeDegree\" "
"ADD FOREIGN KEY (\"ssn\") "
"REFERENCES \"Employee\" "
"INITIALLY DEFERRED");
t.commit ();
}
#else
# error unknown database
#endif
// Create a few persistent objects.
//
{
shared_ptr<employer> st (new employer ("Simple Tech Ltd"));
shared_ptr<employee> john (new employee (1, "John", "Doe", st));
shared_ptr<employee> jane (new employee (2, "Jane", "Doe", st));
john->degrees ().push_back ("BA");
john->degrees ().push_back ("MSc");
jane->degrees ().push_back ("Ph.D.");
transaction t (db->begin ());
db->persist (st);
db->persist (john);
db->persist (jane);
t.commit ();
}
// Load employees with "Doe" as the last name and print what we've got.
//
{
typedef odb::query<employee> query;
typedef odb::result<employee> result;
session s;
transaction t (db->begin ());
result r (db->query<employee> (query::name.last == "Doe"));
for (result::iterator i (r.begin ()); i != r.end (); ++i)
{
cout << i->name ().first () << " " << i->name ().last () << endl
<< " employer: " << i->employer ()->name () << endl;
for (degrees::iterator j (i->degrees ().begin ());
j != i->degrees ().end ();
++j)
{
cout << " degree: " << *j << endl;
}
cout << endl;
}
t.commit ();
}
}
catch (const odb::exception& e)
{
cerr << e.what () << endl;
return 1;
}
}
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