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Lumen - Eloquent: Override name of joining table

I'm building a DB for a software where authentication is coupled with the companys LDAP Server. I now have the two tables

AD_Groups

and

AD_Users

Which are joined in the table 

AD_UsersXAD_Groups

I already learnt about establishing relationships in eloquent. The many to many relationship is exemplified in the official docs by this: https://laravel.com/docs/5.8/eloquent-relationships#many-to-many

Now, as you can see, the following feature of eloquent won't help me much:

"To define this relationship, three database tables are needed: users, roles, and role_user. The role_user table is derived from the alphabetical order of the related model names, and contains the user_id and role_id columns."

I therefore need to override this derived name by using the second parameter, as described here:

"As mentioned previously, to determine the table name of the relationship's joining table, Eloquent will join the two related model names in alphabetical order. However, you are free to override this convention. You may do so by passing a second argument to the belongsToMany method:

return $this->belongsToMany('App\Role', 'role_user');

But as seen in the above example from the docs, the infamous "snake case" is still applied to the name. However, I'm affraid this might not work for my case. Admittedly, AD_UsersXAD_Groups is pretty ugly, and I fear that eloquent/lumen will not be able to correctly identify its elements and apply the snake case rule correctly. But I don't know for sure, and therefore I'm asking you what will be the most likely to work. Using AD_UsersXAD_Groups or AD_UserXAD_Group

Solution

  • Because you have an "x", the Eloquent magic will never be able to match your table automatically.

    You can override the table name in the relationship in your User model. You can also specify the keys if they are not Eloquent's expected "group_id" and "user_id":

    function groups() {
    return $this->belongsToMany(GroupModel::class, 'AD_UsersXAD_Groups', 'user_id_key', 'group_id_key')
}

    And in your Group model you could do this to reverse it

    function users() {
    return $this->belongsToMany(UserModel::class, 'AD_UsersXAD_Groups', 'group_id_key', 'user_id_key')
}