Now, let's imagine we want to retrieve ActivityFeed instances and eager load the parentable parent models for each ActivityFeed instance. Additionally, let's assume that Photo models "have many" Tag models and Post models "have many" Comment models. We will assume the ActivityFeed model defines a "morph to" relationship named parentable that allows us to retrieve the parent Photo or Post model for a given ActivityFeed instance. In this example, let's assume that Photo and Post models may create ActivityFeed models. Eager loading alleviates the 'N+1' query problem. Model::query () returns an instance of this query builder. Eloquent models pass calls to the query builder using magic methods (call, callStatic). However, Eloquent can 'eager load' relationships at the time you query the parent model. 1 Answer Sorted by: 70 Any time you're querying a Model in Eloquent, you're using the Eloquent Query Builder. This means the relationship data is not actually loaded until you first access the property. If you would like to eager load a "morph to" relationship, as well as related model counts for the various entities that may be returned by that relationship, you may utilize the with method in combination with the morphTo relationship's morphWithCount method. When accessing Eloquent relationships as properties, the related models are 'lazy loaded'. We can summarize the relationship's table structure like so:Ĭounting Related Models On Morph To Relationships With all(), you cannot modify the query performed. I do Product::withTrashed()->get() it show 15 products, it is OK. All it does is create a new query object and call get() on it. Exist a way to make a Eloquent Query with trashed but only get a specify ID trashed and all query withoutTrashed For example: I have 15 products in total in database, 10 are not deleted and 5 are trashed. In order to provide support for roles being assigned to multiple users, the role_user table is needed. all() is a static method on the EloquentModel. This would mean that a role could only belong to a single user. Remember, since a role can belong to many users, we cannot simply place a user_id column on the roles table. This table is used as an intermediate table linking the users and roles. The role_user table is derived from the alphabetical order of the related model names and contains user_id and role_id columns. To define this relationship, three database tables are needed: users, roles, and role_user. So, a user has many roles and a role has many users. For example, a user may be assigned the role of "Author" and "Editor" however, those roles may also be assigned to other users as well. An example of a many-to-many relationship is a user that has many roles and those roles are also shared by other users in the application. Many-to-many relations are slightly more complicated than hasOne and hasMany relationships. Return $this -> throughEnvironments () -> hasDeployments () Eloquent makes managing and working with these relationships easy, and supports a variety of common relationships: For example, a blog post may have many comments or an order could be related to the user who placed it.
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