12/29/2023 0 Comments Laravel 5.2 eloquent events![]() 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. 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. We can summarize the relationship's table structure like so:Ĭounting Related Models On Morph To Relationships In order to provide support for roles being assigned to multiple users, the role_user table is needed. The Eloquent collection object extends Laravels base collection, so it naturally inherits dozens of methods used to. If you would like to generate a database migration when you generate the model, you may use the -migration or -m option: php artisan make:model Flight -migration. The easiest way to create a model instance is using the make:model Artisan command: php artisan make:model Flight. ![]() This would mean that a role could only belong to a single user. All Eloquent methods that return more than one model result will return instances of the IlluminateDatabaseEloquentCollection class, including results retrieved via the get method or accessed via a relationship. All Eloquent models extend IlluminateDatabaseEloquentModel class. 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. Eloquent models dispatch several events, allowing you to hook into the following moments in a model's lifecycle: retrieved, creating, created, updating, updated, saving, saved, deleting, deleted, trashed, forceDeleting, forceDeleted, restoring, restored, and replicating. Counting Related Models On Morph To Relationshipsĭatabase tables are often related to one another.Defining Custom Intermediate Table Models.Ordering Queries Via Intermediate Table Columns.Filtering Queries Via Intermediate Table Columns.
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