is_changed on active_model

[kudlatyamroth]

Summary

As of now, we can check if field of active model is changed, but we can't check if anything in whole active model has changed.
It would be great to just check if pear.is_changed() to make updated

Motivation

Now when i have active model and code like that:

async fn update_fruit(id: i64, color: Option<String>) -> Result<(), Error> {
    let apple: Option<fruit::Model> = Fruit::find_by_id(id).one(db).await?;
    let mut apple: Fruit::ActiveModel = apple.unwrap().into();

    if color.is_some() {
        apple.color = Set(color.unwrap());
    }

    let apple: fruit::Model = apple.update(db).await?;

    Ok(())
}

this code will produce error, cos it try to make Update query like that:
update fruit Set Where

With is_changed() method we could make:

if apple.is_changed() {
    apple.update(db).await?;
}

so, no errors will be produced

[billy1624]

Hey @kudlatyamroth, yeah we can definitely add that. Actually, it's just one line of code loll

fruit::Column::iter().all(|col| active_model.get(col).is_changed())