qt实现sqlite3的级联删除

1.需求

2.解决

3.代码

#include "mysql.h"
#include <QtWidgets/QApplication>
#include <QSqlDatabase>
#include <QSqlError>
#include <QSqlQuery>
#include <QtCore/QDir>
#include <QMessageBox>

bool createdb();

int main(int argc, char *argv[])
{
QApplication a(argc, argv);
createdb();

mysql w;
w.show();
return a.exec();
}

bool createdb()
{
bool bret = false;
//这里创建一个db目录存储数据库文件
QString strdbpath("");
strdbpath = QCoreApplication::applicationDirPath();
strdbpath += "/db";
QDir dir("");
dir.mkpath(strdbpath);
strdbpath += "/mysqlite.db";
QSqlDatabase dbset = QSqlDatabase::addDatabase("QSQLITE", "file");
dbset.setDatabaseName(strdbpath);
if (!dbset.open()) {
//LOG_ALL_ERROR(QStringLiteral("failed open mysqlite.db"));
return bret;
}

QSqlQuery setquery(QSqlDatabase::database("file", true));
if(!setquery.exec("PRAGMA foreign_keys = ON;"))
{
QSqlError sqlerror = setquery.lastError();
QString texterr = sqlerror.text();
QMessageBox::information(nullptr, "errormsg", texterr);
return false;
}

//商品详情表
bret = setquery.exec("create table tb_goods(rfid varchar(33) primary key, name varchar(200) not null)");
if (!bret)
{
QSqlError sqlerror = setquery.lastError();
QString texterr = sqlerror.text();
if (texterr.contains("already exists", Qt::CaseInsensitive))
bret = true;
else
{
//LOG_ALL_ERROR(QStringLiteral("failed create table tb_goods."));
return bret;
}
}

//这里条码对照表和skuid对照表因为可能牵涉到多对多的情况 故没有作为主键
//条码对照表
bret = setquery.exec("create table tb_barcode(id INTEGER PRIMARY KEY AUTOINCREMENT, "
"barcode varchar(100) not null, rfid varchar(33) not null, "
"FOREIGN KEY(rfid) REFERENCES tb_goods(rfid)  ON DELETE cascade)");
if (!bret)
{
QSqlError sqlerror = setquery.lastError();
QString texterr = sqlerror.text();
if (texterr.contains("already exists", Qt::CaseInsensitive))
bret = true;
else
{
return bret;
}
}
return bret;
}

#ifndef MYSQL_H
#define MYSQL_H

#include <QtWidgets/QMainWindow>
#include <QSqlQueryModel>
#include "ui_mysql.h"

class mysql : public QMainWindow
{
Q_OBJECT

public:
mysql(QWidget *parent = 0);
~mysql();

private slots:
void on_insertButton_clicked();
void on_deleteButton_clicked();
void on_updateButton_clicked();

private:
void reflushModel();
void setAttibutes(QTableView* pView, int nHeaderHeight = 45, int nColumnHeight = 45);

private:
Ui::mysqlClass ui;
QSqlQueryModel m_goodsmodel;
QSqlQueryModel m_barcodemodel;
};

#endif // MYSQL_H

#include "mysql.h"
#include <QSqlError>
#include <QSqlQuery>
#include <QScrollBar>

mysql::mysql(QWidget *parent)
: QMainWindow(parent)
{
ui.setupUi(this);

m_goodsmodel.setQuery("select * from tb_goods", QSqlDatabase::database("file", true));
m_goodsmodel.setHeaderData(0, Qt::Horizontal, QStringLiteral("id"));
m_goodsmodel.setHeaderData(1, Qt::Horizontal, QStringLiteral("名称"));

m_barcodemodel.setQuery("select * from tb_barcode", QSqlDatabase::database("file", true));
m_barcodemodel.setHeaderData(0, Qt::Horizontal, QStringLiteral("id"));
m_barcodemodel.setHeaderData(1, Qt::Horizontal, QStringLiteral("扫描码"));
m_barcodemodel.setHeaderData(2, Qt::Horizontal, QStringLiteral("rfid"));

ui.goodView->setModel(&m_goodsmodel);
ui.skuidView->setModel(&m_barcodemodel);
setAttibutes(ui.goodView);
setAttibutes(ui.skuidView);
}

mysql::~mysql()
{
}

void mysql::on_insertButton_clicked()
{
QSqlQuery setquery(QSqlDatabase::database("file", true));
setquery.exec("insert into tb_goods values('123456789', 'aaa')");
setquery.exec("insert into tb_goods values('23456789', 'aaeffdda')");

setquery.exec("insert into tb_barcode(barcode,rfid) values('adddaeee', '123456789')");
reflushModel();
}

//这里应该问题不是很大
void mysql::on_deleteButton_clicked()
{
QSqlQuery setquery(QSqlDatabase::database("file", true));
setquery.exec("delete from tb_goods where rfid='123456789'");
reflushModel();
}

void mysql::on_updateButton_clicked()
{
QSqlQuery setquery(QSqlDatabase::database("file", true));
setquery.exec("update tb_goods set name='redddd' where rfid='123456789'");

reflushModel();
}

void mysql::reflushModel()
{
m_goodsmodel.setQuery("select * from tb_goods", QSqlDatabase::database("file", true));
m_barcodemodel.setQuery("select * from tb_barcode", QSqlDatabase::database("file", true));
}

void mysql::setAttibutes(QTableView* pView, int nHeaderHeight, int nColumnHeight)
{
if ( pView == NULL )
{
QString strTemp = QStringLiteral("pView== NULL！设置表格属性失败！");
return;
}

pView->horizontalHeader()->setFixedHeight(nHeaderHeight);               //设置表头的高度
pView->horizontalHeader()->setSectionsClickable(false);                 //设置表头不可点击（默认点击后进行排序）
pView->horizontalHeader()->setStretchLastSection(true);                 //最后一列占满剩余空白
pView->setSelectionBehavior(QAbstractItemView::SelectRows);             //设置选择行为时每次选择一行
pView->setEditTriggers(QAbstractItemView::NoEditTriggers);              //使表视图只读
pView->verticalHeader()->setDefaultSectionSize(nColumnHeight);          //设置行高
pView->setAlternatingRowColors(true);                                   //可以交替颜色显示
pView->setShowGrid(false);                                              //设置不显示格子线
pView->setCornerButtonEnabled(false);                                   //左上角的按钮不可用，此按钮功能，一点击，全选

pView->horizontalScrollBar()->setStyleSheet(
"QScrollBar:horizontal{height:10px;background:transparent;background-color:rgb(248, 248, 248);margin:0px,0px,0px,0px;padding-left:10px;padding-right:10px;}"
"QScrollBar::handle:horizontal{height:10px;background:lightgray;border-radius:5px;/*min-height:20;*/}"
"QScrollBar::handle:horizontal:hover{height:10px;background:gray;border-radius:5px;/*min-height:20;*/}"
"QScrollBar::add-line:horizontal{/*height:10px;width:10px;*/border-image:url(:/button/images/button/right.png);/*subcontrol-position:right;*/}"
"QScrollBar::sub-line:horizontal{/*height:10px;width:10px;*/border-image:url(:/button/images/button/left.png);/*subcontrol-position:left;*/}"
"QScrollBar::add-line:horizontal:hover{/*height:10px;width:10px;*/border-image:url(:/button/images/button/right_mouseDown.png);/*subcontrol-position:right;*/}"
"QScrollBar::sub-line:horizontal:hover{/*height:10px;width:10px;*/border-image:url(:/button/images/button/left_mouseDown.png);/*subcontrol-position:left;*/}"
"QScrollBar::add-page:horizontal,QScrollBar::sub-page:horizontal{background:transparent;border-radius:5px;}"
);

pView->verticalScrollBar()->setStyleSheet(
"QScrollBar:vertical{width:10px;background:transparent;background-color:rgb(248, 248, 248);margin:0px,0px,0px,0px;padding-top:10px;padding-bottom:10px;}"
"QScrollBar::handle:vertical{width:10px;background:lightgray ;border-radius:5px;min-height:20;}"
"QScrollBar::handle:vertical:hover{width:10px;background:gray;border-radius:5px;min-height:20;}"
"QScrollBar::add-line:vertical{height:10px;width:10px;border-image:url(:/button/images/button/down.png);subcontrol-position:bottom;}"
"QScrollBar::sub-line:vertical{height:10px;width:10px;border-image:url(:/button/images/button/up.png);subcontrol-position:top;}"
"QScrollBar::add-line:vertical:hover{height:10px;width:10px;border-image:url(:/button/images/button/down_mouseDown.png);subcontrol-position:bottom;}"
"QScrollBar::sub-line:vertical:hover{height:10px;width:10px;border-image:url(:/button/images/button/up_mouseDown.png);subcontrol-position:top;}"
"QScrollBar::add-page:vertical,QScrollBar::sub-page:vertical{background:transparent;border-radius:5px;}"
);
}

4.备注