Updating calculated gridview field
By default each Active Record class is associated with its database table.
The table Name() method returns the table name by converting the class name via yii\helpers\Inflector::camel2id().
However, most content described here are also applicable to Active Record for No SQL databases.
To get started, declare an Active Record class by extending yii\db\Active Record.
operator so a value will be considered dirty even if it has the same value but a different type.if its value has been modified since it was loaded from DB or saved to DB most recently.Note that data validation will be performed regardless if the Active Record instance has dirty attributes or not.You can do so by calling the yii\db\Active Record::find By Sql() method: Do not call extra query building methods after calling find By Sql() as they will be ignored.As aforementioned, the data brought back from the database are populated into Active Record instances, and each row of the query result corresponds to a single Active Record instance.