打开与Qt/C++的数据库连接

Question

我有MySQL Server8.0 (Workbanch)，我正在尝试使用Qt/C++ (QSqlDatabase)打开一个数据库。但是db.open()总是返回false。为什么？我用的是user: root pass: mypass

Log from terminal:
QSqlDatabase: QMYSQL driver not loaded
QSqlDatabase: available drivers: QSQLITE QMYSQL  
QMYSQL3 QODBC QODBC3 QPSQL QPSQL7
db state:  false

paneldb.cpp

    #include "paneldb.h"
#include "ui_paneldb.h"

PanelDB::PanelDB(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::PanelDB)
{
    ui->setupUi(this);

    db.setHostName("localhost");
    db.setDatabaseName("testdb");
    db.setUserName("root");
    db.setPassword("mypass");

    bool ok = db.open();

    qDebug() << "db state: " << ok;
}

PanelDB::~PanelDB()
{
    delete ui;
}

paneldb.h

    #ifndef PANELDB_H
#define PANELDB_H

#include <QMainWindow>
#include <QSqlDatabase>
#include <QDebug>

namespace Ui {
class PanelDB;
}

class PanelDB : public QMainWindow
{
    Q_OBJECT

public:
    explicit PanelDB(QWidget *parent = nullptr);
    ~PanelDB();

private:
    QSqlDatabase db = QSqlDatabase::addDatabase("QMYSQL");
    Ui::PanelDB *ui;
};

#endif // PANELDB_H

Pro文件：

QT       += core gui
QT       += sql

MYSQL日志：

mysql> SELECT CURRENT_USER();
+----------------+
| CURRENT_USER() |
+----------------+
|   root@localhost |
+----------------+

mysql> SHOW DATABASES;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
| testdb             |
+--------------------+
5 rows in set (0.00 sec)

如何使用QT连接我的数据库？

Answer 1

您必须确保mysql客户端dll位于您的路径中。如果你没有这个，那么你必须先在你的平台上安装它。