Added docs for habtm association about the declaring model referring …

…to zero or more associations

parent f4471fc
author Sandip Mane <sandip.mane@bigbinary.com> 1593247595 +0530
committer Sandip Mane <sandip2490@gmail.com> 1597253412 +0530

Adds doc for habtm association for always optional: true

Added docs line under definition of habtm with a text containing habtm refers to zero or more associations

Added docs line under definition of habtm with a text containing it refers to zero or more associations

Updated the sentence to include declaring association for habtm relation

guides/source/association_basics.md

@@ -118,7 +118,7 @@ end
 ```
 
 When used alone, `belongs_to` produces a one-directional one-to-one connection. Therefore each book in the above example "knows" its author, but the authors don't know about their books.
-To setup a [bi-directional association](#bi-directional-associations) - use `belongs_to` in combination with a `has_one` or `has_many` on the other model. 
+To setup a [bi-directional association](#bi-directional-associations) - use `belongs_to` in combination with a `has_one` or `has_many` on the other model.
 
 `belongs_to` does not ensure reference consistency, so depending on the use case, you might also need to add a database-level foreign key constraint on the reference column, like this:
 
@@ -356,7 +356,9 @@ end
 
 ### The `has_and_belongs_to_many` Association
 
-A `has_and_belongs_to_many` association creates a direct many-to-many connection with another model, with no intervening model. For example, if your application includes assemblies and parts, with each assembly having many parts and each part appearing in many assemblies, you could declare the models this way:
+A `has_and_belongs_to_many` association creates a direct many-to-many connection with another model, with no intervening model.
+This association indicates that each instance of the declaring model refers to zero or more instances of another model.
+For example, if your application includes assemblies and parts, with each assembly having many parts and each part appearing in many assemblies, you could declare the models this way:
 
 ```ruby
 class Assembly < ApplicationRecord