hasManyThrough

A hasManyThrough relationship is a many-to-many relationship. It is used when you want to access a related entity through another entity. The most common example for this is through a pivot table. For instance, a User may have multiple Permissions via a UserPermission entity. This allows you to store additional data on the UserPermission entity, like a createdDate .

// User.cfc
component extends="quick.models.BaseEntity" {

    function permissions() {
       return hasManyThrough( "Permission" );
    }

}

// Permission.cfc
component extends="quick.models.BaseEntity" {

    function users() {
       return hasManyThrough( "User" );
    }

}

// UserPermission.cfc
component extends="quick.models.BaseEntity" {

    function user() {
        return belongsTo( "User" );
    }

    function permission() {
        return belongsTo( "Permission" );
    }

}

The first value passed to hasManyThrough is a WireBox mapping to the related entity.

The second value passed is a WireBox mapping to the intermediate entity.

Quick determines the foreign key of the relationship based on the entity name and key values. In this case, the Permission entity is assumed to have a permissionId foreign key. You can override this by passing a foreign key in as the third argument:

return hasManyThrough("Permission", "UserPermission", "FK_permissionID");

The secondKey is also determined by Quick. It is the foreign key of the current entity for the intermediate entity's table. In our example, this would be userId, since User is our entity and it is for the UserPermissions table. You can override this by passing in the secondKey as the fourth argument.

return hasManyThrough(
    "Permission",
    "UserPermission",
    "FK_permissionID",
    "FK_userID"
);

Lastly, the localKey and secondLocalKey are the primary keys of the entity and the intermediate entities. Usually this is just id. You can override these as the fifth and sixth argument.

return hasManyThrough(
    relationName = "Permission",
    intermeediateName = "UserPermission",
    firstKey = "FK_permissionID", // foreign key on the UserPermission table
    secondKey = "FK_userID", // foreign key on the Permission table
    localKey = "userID", // local key on the owning entity table
    secondLocalKey = "id" // local key on the UserPermission table
);

The inverse of hasManyThrough is also hasManyThrough. A note that the intermediate entity would use belongsTo relationships to link back to each side of the hasManyThrough relationship. These relationships are not needed to use a hasManyThrough relationship.