combining query objects or get union of them - orm

I have a few custom find queries and I would like to combine them.
For example findOwnedBy method returns a query object where a particular customer is owned by a user. findInGroups methods return an other query object where the customer belons to the given group.
I would need to combine these to queries.
I tried the following code
public function findAccessibleBy(Query $query, array $options)
{
$owned = $this->findOwnedBy($query, $options);
$accessViaGroups = $this->findInGroups($query, $options);
}
If I have only the first find I get the correct query in $owned. If I add the second one, than $owned will be empty.
I tried chaning them together and I tried make union of them, but none of these worked.
I am sure I am missing something simple but I do not know what.

Related

What is wrong with how im using this query builder? I'm able to get the records back but it does not order the items

I'm using knex and postgres
I have this handler that calls this query builder. I am able to retrieve the records, however they are not sorting correctly.
What i have:
getStuff(req) {
...
return (toSqlName, builder) =>
builder.whereRaw(`${toSqlName('id')} = ANY(?::uuid[]`, [ids]).orderByRaw('username DESC')
}
Seems to work fine except the records coming back are not sorted. I've tried chaining .orderBy('username', 'desc') as well.

How do I implement, for instance, "group membership" many-to-many in Parse.com REST Cloud Code?

A user can create groups
A group had to have created by a user
A user can belong to multiple groups
A group can have multiple users
I have something like the following:
Parse.Cloud.afterSave('Group', function(request) {
var creator = request.user;
var group = request.object;
var wasGroupCreated = group.existed;
if(wasGroupCreated) {
var hasCreatedRelation = creator.relation('hasCreated');
hasCreatedRelation.add(group);
var isAMemberOfRelation = creator.relation('isMemberOf');
isAMemberOfRelation.add(group);
creator.save();
}
});
Now when I GET user/me with include=isMemberOf,hasCreated, it returns me the user object but with the following:
hasCreated: {
__type: "Relation"
className: "Group"
},
isMemberOf: {
__type: "Relation"
className: "Group"
}
I'd like to have the group objects included in say, 'hasCreated' and 'isMemberOf' arrays. How do I pull that using the REST API?
More in general though, am I approaching this the right way? Thoughts? Help is much appreciated!
First off, existed is a function that returns true or false (in your case the wasGroupCreated variable is always going to be a reference to the function and will tis always evaluate to true). It probably isn't going to return what you expect anyway if you were using it correctly.
I think what you want is the isNew() function, though I would test if this works in the Parse.Cloud.afterSave() method as I haven't tried it there.
As for the second part of your question, you seem to want to use your Relations like Arrays. If you used an array instead (and the size was small enough), then you could just include the Group objects in the query (add include parameter set to isMemberOf for example in your REST query).
If you do want to stick to Relations, realise that you'll need to read up more in the documentation. In particular you'll need to query the Group object using a where expression that has a $relatedTo pointer for the user. To query in this manner, you will probably need a members property on the Group that is a relation to Users.
Something like this in your REST query might work (replace the objectId with the right User of course):
where={"$relatedTo":{"object":{"__type":"Pointer","className":"_User","objectId":"8TOXdXf3tz"},"key":"members"}}

Eloquent: Get pages based on user role

I have a User, Role & Page setup, all with many-to-many relationships and the pivot tables setup in the usual fashion (role_user, page_role), along with the eloquent methods to attach a model to the pivot tables.
My idea is to allow a user to have many roles, and a page can be accessed by many roles.
However now I'd like to return a collection where I have my users details and then the pages they're allowed to access.
The closest I have got is:
return User::find( Auth::user()->id )->with('roles.pages')->first()->roles;
Now this returns each role the user has, and each page that the role can access. Which is correct, however I have duplication on the pages part.
How would I go about getting only a list of pages the user is able to access with no duplication?
Cheers
Read that answer to get you on the track: HasManyThrough with one-to-many relationship
Only for your setup you need to adjust the query - join 2 pivot tables (and make sure they represent real data, ie no rows referencing non-existing models):
// User model
// accessor so you can access it like any relation: $user->pages;
public function getPagesAttribute()
{
if ( ! array_key_exists('pages', $this->relations)) $this->loadPages();
return $this->getRelation('pages');
}
// here you load the pages and set the collection as a relation
protected function loadPages()
{
$pages = Page::join('page_role as pr', 'pr.page_id', '=', 'pages.id')
->join('role_user as ru', 'ru.role_id', '=', 'pr.role_id')
->where('ru.user_id', $this->id)
->distinct()
->get(['pages.*', 'user_id']);
$hasMany = new Illuminate\Database\Eloquent\Relations\HasMany(Page::query(), $this, 'user_id', 'id');
$hasMany->matchMany(array($this), $pages, 'pages');
return $this;
}
One more thing: I hardcoded tables and columns names for sake of simplicity, but in real life I suggest you rely on the relationships and their getters, like: $relation->getTable(), $relation->getForeignKey() etc.
Now suggestion about your code:
return User::find( // 2. query to get the same user
Auth::user()->id // 1. query to get the user and his id
)->with('roles.pages')
->first() // 3. query to get ANOTHER user (or the same, luckily..)
->roles;
Use Auth::id() instead of Auth::user()->id (for Laravel ver 4.1.25+) to avoid redundant query
find() and first() are methods that execute the query, so you just returned the user with id = Auth::user()->id and moment later you fetch another one, who comes first() from the users table..
You don't need to use User::whatever for authenticated user, use Auth::user() instead.
So the code with suggested solution would look like this:
Auth::user()->pages; // collection of Page models with unique entries

Rails ActiveRecord::Relation object using including models

I need to retrieve information from two separate models which are similar but not the same. I am trying to do things like
I have looked into a few methods however they return an array of active objects rather than an
ActiveRecord::Relation which is required for many of the features of my app to work.
Is there any way to return an ActiveRecord::Relation object containing a union of both tables?
I have tried things like
#group = Mymodel.find_by_sql("SELECT id FROM Mymodels
UNION SELECT id FROM AnotherModels")
and also explored using the Model.where method however cannot return an ActiveRecord::Relation
EDIT:
Just to be clear I need to return ActiveRecord::Relation that is a union or a merge of the two tables
Have you tried MyFirstModel.joins(:my_second_models)? Check out details joins in the API here.
EDIT: Single Table Inheritance is a better solution to this problem. See comments below.
Try something like this:
Model.joins(:other_model).where("attr1" = :attr1,
{ attr1: "example" }).group(:attr1)
Since you commented about where, I added the where method on the call. You can also group everything using :group in the end.

kohana ORM question

i am using kohana ORM in order to get some results from the database. My problem is: even though i have consulted the documentation, i can't find a way to select only the column i am interested in. To be more explicit, i have:
$sale_stock = Model::factory('product_type')
->where('product_type_id','=', $id )
-> find_all();
var dumping it, it selects me all the "SELECT product_type.* from product_type where etc".
But i want to select only the 'stock' field from the salestock table. doing find('stock') instead find_all() returns a weired object... Where am i wrong, and how can i actually select only the column 'stock' using kohana orm?
thank you!
ORM methods find() and find_all() always select all table columns, so there is two ways to get specified fields:
Load full table rows and get columns
from it:
$sale_stock = Model::factory('product_type')
->where('product_type_id','=', $id )
-> find_all();
// get array of id=>stock values
$columns = $sale_stock->as_array('id', 'stock');
Create special method in model using
Query Builder:
// model Model_Product_Type
public function get_stocks($product_type_id)
{
return DB::select(array('stock'))
->from($this->_table_name)
->where('product_type_id', '=', $product_type_id)
->execute($this->_db);
}
I realise this isn't exactly what you're looking for, but I've pulled the following from the Kohana documentation ...
$articles = ORM::factory('article')->select_list('id', 'title');
foreach ($articles as $id => $title)
{
// Display a list of links
echo html::anchor('articles/'.$id, $title);
}
// Display a dropdown list
echo form::dropdown('articles', $articles);
You could think of it as a discount, two fields for the price of one.
It's common practice for ORMs to return a 'non-standard' object when partial model or merged model fields are requested. This prevents confusing operations using the original object (ie. how do you save an object when it contains only 2 of 8 fields, plus maybe some fields from another model?).
If you print_r the object, and give me an indication of how that looks ... it might be just what you want.
I know this is an old question, but i found maybe easier solution:
$sale_stock = ORM::factory('product_type')
->where( 'product_type_id','=', $id )
->find_all();
die($sale_stock->stock);