QT连接MYSQL数据库的详细步骤

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//添加mysql数据库

QSqlDatabase db=QSqlDatabase::addDatabase("QMYSQL");

//连接数据库

db.setHostName("127.0.0.1");//数据库服务器IP

db.setUserName("root"); //数据库用户名

db.setPassword("root");//数据库用户名密码

db.setDatabaseName("sys"); //数据库名

if(db.open()==false)

{

QMessageBox::information(this,"数据库打开失败",db.lastError().text());

return;

}

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QSqlQuery q;

q.exec("create table student(id int primary key auto_increment, name varchar(255), age int, score int)ENGINE=INNODB;");

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q.exec("insert into student(id, name, age,score) values(1, '张三', 24,80);");

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q.prepare("insert into student(name, age,score) values(?, ?, ?)"); //?是占位符

QVariantList name;

name<<"素数"<<"等待"<<"安安";

QVariantList age;

age<<-2<<12<<14;

QVariantList score;

score<<0<<89<<90;

//给字段绑定相应的值 按顺序绑定

q.addBindValue(name);

q.addBindValue(age);

q.addBindValue(score);

//执行预处理命令

q.execBatch();

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//占位符 :+自定义名字

q.prepare("insert into student(name, age,score) values(:n, :a,:s)");

QVariantList name;

name<<"夸克"<<"红米"<<"鸿蒙";

QVariantList age;

age<<5<<10<<3;

QVariantList score;

score<<77<<89<<99;

//给字段绑定 顺序任意因为根据:+自定义名字

q.bindValue(":n",name);

q.bindValue(":s",score);

q.bindValue(":a",age);

//执行预处理命令

q.execBatch();

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QSqlQuery q;

q.exec("update student set score=76 where name='李四'");

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QSqlQuery q;

q.exec("delete from student where name='张三'");

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QSqlQuery q;

q.exec("select *from student");

while(q.next()) //遍历完为false

{

//以下标

//qDebug()<<q.value(0).toInt()<<q.value(1).toString()<<q.value(2).toInt()

<<q.value(3).toInt();

//以字段

qDebug()<<q.value("id").toInt()<<q.value("name").toString()<<q.value("age").toInt()

<<q.value("score").toInt();

}