drop、truncate、 delete区别
最基本：
● drop直接删掉表。
● truncate删除表中数据，再插入时自增长id又从1开始。
● delete删除表中数据，可以加where字句。

drop,truncate,delete区别

    showDetail = new ShowDetail(ui->stackedWidget->widget(2));
    showDetail->move(60,155);

qt ui文件内嵌入ui文件

下载nexus
https://www.sonatype.com/products/sonatype-nexus-oss-download
https://download.sonatype.com/nexus/3/latest-unix.tar.gz
```bash
wget https://download.sonatype.com/nexus/3/latest-unix.tar.gz
tar -zxvf latest-unix.tar.gz 
```
运行nexus
```bash
root@iZj6ccbk1bxo1f33sa7xgyZ:/www/wwwroot/mirrors.momen.world/nexus-3.59.0-01/bin# ./nexus start
WARNING: ************************************************************
WARNING: Detected execution as "root" user.  This is NOT recommended!
WARNING: ************************************************************
Starting nexus
root@iZj6ccbk1bxo1f33sa7xgyZ:/www/wwwroot/mirrors.momen.world/nexus-3.59.0-01/bin# ./nexus status
WARNING: ************************************************************
WARNING: Detected execution as "root" user.  This is NOT recommended!
WARNING: ************************************************************
nexus is running.
root@iZj6ccbk1bxo1f33sa7xgyZ:/www/wwwroot/mirrors.momen.world/nexus-3.59.0-01/bin# 
```
https://blog.csdn.net/qq_44214446/article/details/128272077
查看nexus属性文件
nexus-3.59.0-01/etc$ cat nexus-default.properties 
创建gpg密钥对
`gpg --gen-key`
打印密钥信息
`gpg --list-keys`
导出并查看公钥
`gpg -a -o [密钥uid]_pub.asc --export [密钥uid]`
导出并查看私钥
`gpg -a -o [密钥uid]_pri.asc --export-secret-key [密钥uid]`

部署nexus仓库

https://help.aliyun.com/zh/oss/developer-reference/ossfs-installation?spm=a2c4g.11186623.0.0.1a4a2e48AHikk7#concept-kkp-lmb-wdb
1. Ubuntu20.04 下载ossfs
https://gosspublic.alicdn.com/ossfs/ossfs_1.91.1_ubuntu20.04_amd64.deb?spm=a2c4g.11186623.0.0.14074ea29LZZsk&file=ossfs_1.91.1_ubuntu20.04_amd64.deb

`sudo echo [oss bucket名]:[阿里云accesskey]:[阿里云accesskey Security] > /etc/passwd-ossfs`
`sudo chmod 640 /etc/passwd-ossfs`
`sudo mkdir /tmp/ossfs`
`sudo ossfs spark-drivermanagement /tmp/ossfs -o url=https://oss-cn-hongkong-internal.aliyuncs.com`

轻量服务器挂载oss

按下按钮打断某函数的执行
场景：读卡机循环读卡，现在需要外部打断
之前：
```c++
while(1){
    read();
}
```
用时钟，每1s触发一次函数，按按钮停止
```c++
#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QPushButton>
#include <QTimer>

QT_BEGIN_NAMESPACE
namespace Ui { class MainWindow; }
QT_END_NAMESPACE

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    MainWindow(QWidget *parent = nullptr);
    ~MainWindow();

private slots:
    void outputText();
    void stopLoop();

private:
    Ui::MainWindow *ui;
    QTimer *timer;
    QPushButton *stopButton;
};

#endif // MAINWINDOW_H

#include "mainwindow.h"
#include "ui_mainwindow.h"

#include <QTimer>

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

    // 创建定时器
    timer = new QTimer(this);
    connect(timer, &QTimer::timeout, this, &MainWindow::outputText);

    // 创建按钮
    stopButton = new QPushButton("Stop", this);
    stopButton->setGeometry(10, 10, 80, 30);
    connect(stopButton, &QPushButton::clicked, this, &MainWindow::stopLoop);

    // 启动定时器
    timer->start(1000); // 每秒触发一次timeout信号
}

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

void MainWindow::outputText()
{
    ui->textEdit->append("1");
}

void MainWindow::stopLoop()
{
    timer->stop(); // 停止定时器，终止循环输出
    ui->textEdit->append("Loop stopped.");
}
```

---

开线程进行操作，按按钮断掉线程(来源gpt)
```c++
#include "mainwindow.h"
#include "ui_mainwindow.h"

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

    // 创建按钮
    stopButton = new QPushButton("Stop", this);
    stopButton->setGeometry(10, 10, 80, 30);
    connect(stopButton, &QPushButton::clicked, this, &MainWindow::stopLoop);

    // 启动循环线程
    loopThread = new LoopThread(this);
    connect(loopThread, &LoopThread::textOutput, this, &MainWindow::outputText);
    loopThread->start();
}

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

void MainWindow::outputText(const QString &text)
{
    ui->textEdit->append(text);
}

void MainWindow::stopLoop()
{
    loopThread->stop();
    ui->textEdit->append("Loop stopped.");
}
#include "loopthread.h"

LoopThread::LoopThread(QObject *parent) : QThread(parent), running(true)
{

}

void LoopThread::run()
{
    while (running) {
        emit textOutput("1");
        msleep(1000); // 等待1秒
    }
}

void LoopThread::stop()
{
    running = false;
}
#ifndef LOOPTHREAD_H
#define LOOPTHREAD_H

#include <QThread>

class LoopThread : public QThread
{
    Q_OBJECT
public:
    explicit LoopThread(QObject *parent = nullptr);

signals:
    void textOutput(const QString &text);

public slots:
    void stop();

protected:
    void run() override;

private:
    bool running;
};

#endif // LOOPTHREAD_H

```