💅 for migrations guide from rails#15457 [ci skip]

Author: Zachary Scott

guides/source/migrations.md

@@ -417,25 +417,26 @@ column and adds an index on it. Finally it renames the `upccode` column.
 
 ### Changing Columns
 
-Like the `remove_column` and `add_column` Rails provides the `change_column`.
+Like the `remove_column` and `add_column` Rails provides the `change_column`
+migration method.
 
 ```ruby
 change_column :products, :part_number, :text
 ```
 
-This changes the column part_number on products table to be a text.
+This changes the column `part_number` on products table to be a `:text` field.
 
-Besides the `change_column`, the `change_column_null` and
-`change_column_default` are used specifically to change the null and default
-values of a column.
+Besides `change_column`, the `change_column_null` and `change_column_default`
+methods are used specifically to change the null and default values of a
+column.
 
 ```ruby
 change_column_null :products, :name, false
 change_column_default :products, :approved, false
 ```
 
-This sets name on products to a NOT NULL column and the default value
-of approved as false.
+This sets `:name` field on products to a `NOT NULL` column and the default
+value of the `:approved` field to false.
 
 ### When Helpers aren't Enough