Rewrite Relations user guide and update screen shots

Signed-off-by: Isaac Bennetch <bennetch@gmail.com>

Author: ibennetch

docs/images/pma-relations-category.png

@@ -28,7 +28,7 @@ Relation view
 -------------
 
 In order to get it working, you first have to properly create the
-[[pmadb|pmadb]]. Once that is setup, select a table's "Structure" page. Below
+:ref:`linked-tables`. Once that is setup, select a table's "Structure" page. Below
 the table definition, a link called "Relation view" is shown. If you click that
 link, a page will be shown that offers you to create a link to another table
 for any (most) fields. Only PRIMARY KEYS are shown there, so if the field you
@@ -39,27 +39,43 @@ record.
 Relation view example
 +++++++++++++++++++++
 
+Let's say you have a database with employees and their departments. Your table structure would be something like this:
+
+-   ``employees.id`` (must be unique)
+-   ``employees.name``
+-   ``employees.department``
+-   ``departments.dept_id``
+-   ``departments.department_name``
+
+Each employee belongs to only one department, but each department has many employees.
+Of course you might also have fields in ``employees`` for things like email address and office number as well as
+a third table for current projects or supervisor or any of many other possible details.
+
 .. image:: images/pma-relations-relation-view-link.png
 
 .. image:: images/pma-relations-relation-link.png
 
-Let's say you have categories and links and one category can contain several links. Your table structure would be something like this:
+From the ``employees`` table :guilabel:`Structure` tab, open the :guilabel:`Relation view` (just below the menu bar). Select the ``department`` column
+as the column to work with and ``departments`` table ``dept_id`` column as that is the referenced key.
+We recommend using the native constraints where possible, but there is an :guilabel:`Internal relationships` area for usage when
+the table type does not support these natively.
 
--   `category.category_id` (must be unique)
--   `category.name`
--   `link.link_id`
--   `link.category_id`
--   `link.uri`.
+If you now browse the ``employees`` table, the ``department`` field will be a clickable hyperlink to the proper category record. It will still show the
+``dept_id`` instead of the label. A tooltip appears when hovering over the values with the referenced label.
 
-Open the relation view (below the table structure) page for the `link` table and for `category_id` field, you select `category.category_id` as master record.
+.. image:: images/pma-relations-links.png
 
-If you now browse the link table, the `category_id` field will be a clickable hyperlink to the proper category record. But all you see is just the `category_id`, not the name of the category.
+To further improve this, open the :guilabel:`Relation view` of the ``departments`` table and in the drop down at the bottom, select
+``department_name`` (in some cases, this may already be the default setting).
 
 .. image:: images/pma-relations-relation-name.png
 
-To fix this, open the relation view of the `category` table and in the drop down at the bottom, select "name". If you now browse the link table again and hover the mouse over the `category_id` hyperlink, the value from the related category will be shown as tooltip.
+Go back to the :guilabel:`Browse view` for the ``employees`` table and expand the :guilabel:`Extra options` then select
+:guilabel:`Display column for relationships`. This shows the text from the referenced table instead of the integer value.
 
-.. image:: images/pma-relations-links.png
+.. image:: images/pma-relations-display-column.png
+
+This preference can be set in :config:option:`$cfg['RelationalDisplay']` or the user preferences.
 
 Designer
 --------
@@ -74,6 +90,9 @@ must have the :config:option:`$cfg['Servers'][$i]['table_coords']` configured.
 To use the designer, select a database's structure page, then look for the
 :guilabel:`Designer` tab.
 
+.. image:: images/pma-relations-designer.png
+
+You can also export this window, which can be handy to visually reference the database structure.
 To export the view into PDF, you have to create PDF pages first. The Designer
 creates the layout, how the tables shall be displayed. To finally export the
 view, you have to create this with a PDF page and select your layout, which you