Behavior for support relational data management.

• Insert related models from POST array.
• Delete related models from database which not exist in POST array
• Skip related models which already exist in database with same attributes
• Rollback database changes, if relational model save/delete error occurred
• Support one-to-one and one-to-many relations

This behavior uses getters for relational attribute in owner model, such getters must return ActiveQuery object. If you use string values in ON condition in ActiveQuery object, then this behavior will throw exception.

composer require notamedia/yii2-relation