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. 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. The result set is returned as an Eloquent Collection, an iterable object that behaves similarly to an array, but provides extended functionality such as map / reduce methods and the ability to hydrate (pull in fresh data) referenced objects only when needed, which helps with overall performance while interacting with the database. 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. 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.Method-3: Combining IN query with relationships. Filtering Queries Via Intermediate Table Columns Method-2: Prepending the whereIn method with the select method.So when you're outputting your collection as JSON you're seeing it represented as an object.Ī way to ignore the keys in the collection is to use values, so that a new collection is created (with ascending numeric keys i.e. In PHP, if your array keys aren't integers, in ascending order starting from 0, it is assumed to be an associative array. So in this case you'll be seeing the last item, first and the keys will be 9, 8, 7. The reverse method creates a new collection, but preserves the keys of the original collection. You're getting the same collection back, in reverse order. Now when you're doing: $eventi = \App\Model::with('relation_1', 'relation_2') It will then be accessible via a dynamic property by the same name as the relation. Eloquent will automatically load the relationship for you, and is even smart enough to know whether to call the get (for one-to-many relationships) or first (for one-to-one relationships) method. The keys of the values in the underlying array will be numeric, i.e. Eloquent allows you to access your relations via dynamic properties. You get a Collection object, containing those values. When you do this: $eventi = \App\Model::with('relation_1', 'relation_2')
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