我正在尝试为一个项目学习 Wt,现在我正在尝试学习其中的数据库部分。
我一开始就卡住了。我正在尝试从 dbo 教程中学习它(网站http://www.webtoolkit.eu/wt/doc/tutorial/dbo/tutorial.html#_installing_tt_wt_dbo_tt中有一个教程),该教程位于示例中wt包(tutorial1.C)
我在 ubuntu 中使用 Qt 编译器(5.)。正如网站教程(上面链接)中所说,我已经构建了 Wt::Dbo 库。问题是它仍然给出一个错误;
找不到 lGL
collect2:ld 返回 1 个退出状态
这是Wt中的代码(直接从tutorial1.C复制)
/*
* Copyright (C) 2010 Emweb bvba, Kessel-Lo, Belgium.
*
* See the LICENSE file for terms of use.
*/
/*****
* This file is part of the Wt::Dbo tutorial:
* http://www.webtoolkit.eu/wt/doc/tutorial/dbo/tutorial.html
*****/
#include <Wt/Dbo/Dbo>
#include <Wt/Dbo/backend/Sqlite3>
#include <string>
namespace dbo = Wt::Dbo;
/*****
* Dbo tutorial section 2. Mapping a single class
*****/
class User {
public:
enum Role {
Visitor = 0,
Admin = 1,
Alien = 42
};
std::string name;
std::string password;
Role role;
int karma;
template<class Action>
void persist(Action& a)
{
dbo::field(a, name, "name");
dbo::field(a, password, "password");
dbo::field(a, role, "role");
dbo::field(a, karma, "karma");
}
};
void run()
{
/*****
* Dbo tutorial section 3. A first session
*****/
/*
* Setup a session, would typically be done once at application startup.
*
* For testing, we'll be using Sqlite3's special :memory: database. You
* can replace this with an actual filename for actual persistence.
*/
dbo::backend::Sqlite3 sqlite3(":memory:");
sqlite3.setProperty("show-queries", "true");
dbo::Session session;
session.setConnection(sqlite3);
session.mapClass<User>("user");
/*
* Try to create the schema (will fail if already exists).
*/
session.createTables();
{
dbo::Transaction transaction(session);
User *user = new User();
user->name = "Joe";
user->password = "Secret";
user->role = User::Visitor;
user->karma = 13;
dbo::ptr<User> userPtr = session.add(user);
}
/*****
* Dbo tutorial section 4. Querying objects
*****/
{
dbo::Transaction transaction(session);
dbo::ptr<User> joe = session.find<User>().where("name = ?").bind("Joe");
std::cerr << "Joe has karma: " << joe->karma << std::endl;
dbo::ptr<User> joe2 = session.query< dbo::ptr<User> >
("select u from user u").where("name = ?").bind("Joe");
}
{
dbo::Transaction transaction(session);
typedef dbo::collection< dbo::ptr<User> > Users;
Users users = session.find<User>();
std::cerr << "We have " << users.size() << " users:" << std::endl;
for (Users::const_iterator i = users.begin(); i != users.end(); ++i)
std::cerr << " user " << (*i)->name
<< " with karma of " << (*i)->karma << std::endl;
}
/*****
* Dbo tutorial section 5. Updating objects
*****/
{
dbo::Transaction transaction(session);
dbo::ptr<User> joe = session.find<User>().where("name = ?").bind("Joe");
joe.modify()->karma++;
joe.modify()->password = "public";
}
{
dbo::Transaction transaction(session);
dbo::ptr<User> joe = session.find<User>().where("name = ?").bind("Joe");
if (joe)
joe.remove();
}
{
dbo::Transaction transaction(session);
dbo::ptr<User> silly = session.add(new User());
silly.modify()->name = "Silly";
silly.remove();
}
}
int main(int argc, char **argv)
{
run();
}
提前致谢