Yii2框架数据库增删改查

Posted 2021-06-23 天行子

查询操作：

User::find()->one();    //返回一条数据；
User::find()->all();    //返回所有数据；
User::find()->count();    //返回记录的数量；
User::find()->average();   //返回指定列的平均值；
User::find()->min();    //返回指定列的最小值 ；
User::find()->max();   //返回指定列的最大值 ；
User::find()->scalar();    //返回值的第一行第一列的查询结果；
User::find()->column();    //返回查询结果中的第一列的值；
User::find()->exists();    //返回一个值指示是否包含查询结果的数据行；

User::find()->where([\'name\' => \'username\'])->one();   此方法返回 [\'name\' => \'username\'] 的一条数据；
User::find()->where([\'name\' => \'username\'])->all();   此方法返回 [\'name\' => \'username\'] 的所有数据；
User::find()->andWhere([\'sex\' => \'男\', \'age\' => \'24\'])->count(\'id\');   统计符合条件的总条数；
$student = Student::find()->where([\'status\'=>ConfigHelper::STATUS_ABLE])->count();
$student = Student::findOne(7688);
$student =(new Query())->from(\'student\')->select([\'id\',\'username\'])->where([\'id\'=>7688])->one();

$connection = Yii::$app->db;
$sql = "select * from student limit 1";
$student = $connection->createCommand($sql)->queryAll();

$sql = \'SELECT * FROM student limit 10\';
 $student = Student::findBySql($sql)->asArray()->all();

each查询

 $query = (new Query())->from(\'student\')->where([\'classes_id\'=>6])->batch(10);

echo \'<pre>\';
foreach ($query as $students){
    var_dump($students);
}

batch查询

$query = (new Query())->from(\'student\')->where([\'classes_id\'=>6])->each(10);
echo \'<pre>\';
foreach ($query as $students){
    var_dump($students);
}

新增操作：

$model = newUser();
$model->username = \'username\';
$model->age      = \'20\';
$model->insert();

$connection = Yii::$app->db;
$r = $connection->createCommand()
->insert(\'classes\',[\'name\'=>\'class\',\'school_id\'=>67843,\'comment\'=>\'test\',\'is_pay\'=>0,\'account_type_id\'=>2])
->execute();

$class = new Classes();
$class->name = \'class2\';
$class->school_id = 67843;
$r = $class->save();

批量插入

$connection = Yii::$app->db;
$r = $connection->createCommand()
->batchInsert(\'classes\',[\'name\',\'school_id\'],[[\'class3\',\'67843\'],[\'class4\',\'67843\']])
->execute();

修改操作：

$User = User::findOne($id);
$User->name = \'zhangsan\';
$User->save(); // 等同于 $User->update();

删除操作：

User::deleteAll(\'name = username\');    删除 name = username 的数据；
User::findOne($id)->delete(); 删除主键为 $id变量 值的数据库；
User::deleteAll(\'age > :age AND sex = :sex\', [\':age\' => \'20\', \':sex\' => \'1\']);  删除符合条件的数据；