Summary of addition, deletion, modification and query of Yii2 framework database

User::find()->all(); //Return all user data;
User::findOne($id); //Return a piece of data with primary key id=1;
User::find()- >where(['name' => 'ttt'])->one(); //Return a piece of data from ['name' => 'ttt'];
User::find()-> ;where(['name' => 'ttt'])->all(); //Return all data of ['name' => 'ttt'];
User::findBySql('SELECT * FROM user')->all(); //Use sql statement to query all data in the user table;
User::findBySql('SELECT * FROM user')->one(); This method uses sql statement to query A piece of data in the user table;
User::find()->andWhere(['sex' => 'Female', 'age' => '18'])->count('id') ; //Count the total number of items that meet the conditions;
User::find()->one(); //Return one piece of data;
User::find()->all(); //Return all data ;
User::find()->count(); //Returns the number of records;
User::find()->average(); //Returns the average of the specified column;
User::find ()->min(); //Return the minimum value of the specified column;
User::find()->max(); //Return the maximum value of the specified column;
User::find()-> ;scalar(); //Return the query result of the first row and first column of the value;
User::find()->column(); //Return the value of the first column in the query result;
User: :find()->exists(); //Returns a value indicating whether the data row contains the query result;

Query operation:

User::find()->where(['name' => 'username'])->one(); This method returns a piece of data from ['name' => 'username'];
User::find()->where(['name' => 'username'])->all(); This method returns all data of ['name' => 'username'];

User::find()->andWhere(['sex' => 'Male', 'age' => '24'])->count('id'); Count the total number of items that meet the conditions Number;

New operation:

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

Modification operation:
$User = User::findOne($id);
$User->name = 'zhangsan';
$User->save(); // Equivalent to $User-> update();

Delete operation:

User::deleteAll('name = username'); Delete the data with name = username;
User::findOne($id)->delete(); Delete the database whose primary key is the value of the $id variable;
User:: deleteAll('age > :age AND sex = :sex', [':age' => '20', ':sex' => '1']); Delete data that meets the conditions;