Replace relationship definitions to cover all the bases and so Relation plays well with Views

Terrific idea.

I must presume you meant this patch. I can't seem to be able to pick r_index though.

There

+++ b/views/relation.views.incundefined
@@ -189,60 +193,68 @@ function relation_views_data_alter(&$data) {
-            'handler' => 'views_handler_relationship',

You can't have a relationship without a handler. Maybe an issue for views should be filled...

Here is a new patch

Right now, the biggest problem is that I do not readily see how to add the relation table itself. Otherwise, we are good.

We are getting closer.

Thanks for the work, what we have in contrib works. To some extent. There are a few problems: you can't get to the relation table and you need to make that chainable , as a base table isn't enough because you can have E1-R1-E2-R2-E3. Also if you have node --> user then you can't get from user to anywhere.

Was doing a "1->many" of "users->nodes" using a view of users and a "Provides a relationship from @left(users) to @right(nodes) via the relation @relation_type_label" relationship

Since the 06/12/2011 4:24:44 pm commit this has been removed and it seems the replacement is meant to be "@left(users) to the other endpoints(nodes) using the "@relation_type_label" relation"
However this option is not appearing as a Relationship option in my view of users

After creating a relation view the only available relationships group was "Relation", there was not the option of "Entity"

Yeah there is no entity group (and solotandem thought of endpoints, anwyays). Everything is in the relation group. Read the title/description carefully, they tell you quite a lot. I also worked on them a lot to be so. Also, it's being heavily worked on, so within a short term it might be a lot better.

Seems to work for me now with this patch.

I have a directional relation called Participants between nodes (representing courses) and users. I wanted to have a view to pull the users attached a particular course; after some messing around, I was able to to it by creating the 3 following relationships:

Relation: Participants (endpoints -> user)
(Endpoints::Participants) Relation: Participants (endpoints -> endpoints)
(Endpoints::Participants) Relation: Endpoints: Participants (endpoints -> node)

EDIT:

In addition, I am now also able to do it directly from a view using the user table as its basis (instead of relation), so that's even better:

User: Endpoints: Participants (user -> endpoints)
(Endpoints::Participants) Relation: Participants (endpoints -> endpoints)
(Endpoints::Participants2) Relation: Endpoints: Participants (endpoints -> node)

Thanks

I'm using current version of the Relation module(15 dec). Are this patches are applied in my version ? Earlier I could get RID field, after update I can't get this field...

// Update

I can add only "endpoints" field. Fields like RID,VID, Relation Type, UID, Created etc. can't be added. I think it is caused table group name change but Im now an expert in Relation module.

$data['field_data_endpoints']['table']['group'] = t('Relation');
$data['field_data_endpoints']['table']['join'] = array();

Ok I created new issue -> http://drupal.org/node/1372956.

Any advice/patch/whatever is very important to me. I'm fighting with views in Relation for a long time. After each update I have new problems...

There's a whole + // Define join from entity to endpoints. section commented out. Also, there are no tests :(

Thanks for providing the missing definitions!

Re #14, I think I undertand the concept, but I don't see how to make the middle views relationship: the one going from endpoints -> endpoints.

In my case, I have students and organizations as node entities, and internships as relations. Internships have some fields like year (taxonomy) and final report (file field). I need to display a list of students and information about their internships (organization name, year, and final report). Not all students have internships, so I can't base the view off the internship relation.

Here are the three views relationship options I am currently seeing (I have applied patch #19):

Relation: endpoints[internship] -> node) Endpoints table to node using "internship" relation
Relation: interns with -> endpoints[internship] Relation table to endpoints table using "internship" relation
Relation: node -> endpoints[internship]) node to the sibling endpoints using the "internship" relation

Nothing obvious there about relating endpoints to endpoints. I'm not sure what the second one ("Relation table to endpoints table") does. Is that the "end points -> end points" views relation? I don't see an option to base it on the previously created node->endpoints.

Thanks

I figured #20 out - failed to clear views cache after applying the patch! It seems to be working - so far so good, anyway. Thanks!

The last patch at #19 work for me. But we need add "relation type" condition (column bundle of table "field_data_endpoints") on the first JOIN clause from endpoints to "left" entity.

// Define join from endpoints to "left" entity.
 $data['field_data_endpoints']['table']['join'] += array(
// Directly links to the $entity_type_right table.
$entity_type_left => array(
   'left_field' => $entity_infos[$entity_type_left]['entity keys']['id'],
   'field' => 'endpoints_entity_id',
   ),
 );

Because between 2 entity type (or entity type:bundle) have many relation types so we must specific relation type for the select query

I try to create relationship from "endpoints ---> relation" and then filter by "Relation type" and "r_index" but the query omit entities (left side) if it do not have relation with "right side" entities instead of result in NULL
So, add "Relation type" condition at first join from endpoints to "left" entity will retain the entities (left side) that do not have relation with "right side"
---> JOIN clause in #19 comment <-----
LEFT JOIN {field_data_endpoints} field_data_endpoints ON A.id = field_data_endpoints.endpoints_entity_id

---> My JOIN clause <-----
LEFT JOIN {field_data_endpoints} field_data_endpoints ON A.id = field_data_endpoints.endpoints_entity_id AND field_data_endpoints.bundle = 'relation_type1'

Change in this patch:
1. Add join handler in relation.views.inc (relation_handler_endpoint_entity_join)
2. Declare file in relation.info
3. Define join handler class in file "relation_handler_endpoint_entity_join"

Ignore #22 patch

Post lasted patch

It works perfectly, great job!

While it's true working with relations requires a rather complicated string of Views relationships (inner joins), it's really the best way to accomplish this. Maybe a training video should be in order.

I'm not quite sure if I'm on the map with the scope of this issue but my observations are the following(with a patch from #23): I have simple view listing users and I add new relationship user -> endpoints of relation type X. SQL as a result:

SELECT users.name AS users_name
FROM 
{users} users
INNER JOIN {field_data_endpoints} field_data_endpoints_users ON users.uid = field_data_endpoints_users.endpoints_entity_id

The relationships list shows these joins per relation type but the resulting query matches endpoints of all relations and all entity types. When you proceed from endpoints to relation or whatever the query can't make difference between user/1 and node/1 for example.

Only way to get the bundle added to query is by picking directional relation and then choosing position of the relationship base for it.

@mikran

To get the bundle added to query is by picking directional relation and then choosing position of the relationship base for it

. I think this is not a appropriate way to get the correct result because the query will add bundle condition on the "second" field_data_endpoints table (regular alias "field_data_endpoints_field_data_endpoints")

Eg:

• I have a directional relation between node:article & node:page name "article_to_page".
• I have an article (node/1) as my input and i want to get all node:page that have relation with article (node/1) at relation type "article_to_page".

My view config:

1. Add relationship "Article to page (endpoints -> endpoints)" and select "Position of the relationship base" = "target"

The sql query is:

SELECT node.title AS node_title, node.nid AS nid
FROM 
{node} node
LEFT JOIN {field_data_endpoints} field_data_endpoints ON node.nid = field_data_endpoints.endpoints_entity_id
LEFT JOIN {field_data_endpoints} field_data_endpoints_field_data_endpoints ON field_data_endpoints_field_data_endpoints.entity_id = field_data_endpoints.entity_id AND field_data_endpoints_field_data_endpoints.endpoints_r_index != field_data_endpoints.endpoints_r_index AND field_data_endpoints_field_data_endpoints.endpoints_r_index = 1 AND field_data_endpoints_field_data_endpoints.endpoints_entity_type = 'node' AND field_data_endpoints_field_data_endpoints.bundle = 'article_to_page'

This query does not result the exact node:page that have relation with article (node/1) at relation type "article_to_page".
This is detail result run in phpmyadmin

Okay, here is a patch that fixes the scenario I had. These conditions probably have to be extended to endpoints -> endpoints joins as well.

The added file 'views/relation_handler_endpoint_entity_join.inc' is in separate patch file as I didn't figure out how to put it to same file.

Whitespace error fixed and now I figured out how to put everything into single file :).

Some more test results:

Chain:
1. entity -> endpoint (works)
2. endpoint -> endpoint (works)
-2.1 endpoint -> relation (does not work, uses entity_id whereas endpoints_entity_id is what we are looking for)
-2.2 endpoint -> entity (does not work, uses correct field 'endpoints_entity_id' but 'bundle' and 'endpoints_entity_type' are not included)

How about this one then
Using #19 I have a directional relationship from All users bundles > Nodes of type test
Starting with a view showing Relations, relationships can be build and work fine
However starting with a view of Users no relationships (pertaining to this module) are available

To play nice with Views, it is enough to stick to the original implementation but move the logic into the query method of the relationship handler and use the Views API properly instead of DBTNG.

So just to clarify
Does this mean that views integration has been rewritten and is now "playing nicely" again?

I'm lost as well. Is there a follow up issue somewhere? What happens with the patches we've been running with that we need to make Relation work?

I think this is chx's way of saying "fixed, but it a slightly different way". See commit e8e00ad

Confirmed. I was able to make the view function using the latest version of the project, and it only required TWO relationships.

Add clarification.