1 files changed, 12 insertions, 5 deletions
diff --git a/guides/source/active_record_querying.textile b/guides/source/active_record_querying.textile
index 14d0ba9b28..98937266ba 100644
--- a/guides/source/active_record_querying.textile
+++ b/guides/source/active_record_querying.textile
@@ -388,6 +388,8 @@ The field name can also be a string:
 Client.where('locked' => true)
 </ruby>
 
+NOTE: The values cannot be symbols. For example, you cannot do +Client.where(:status => :active)+.
+
 h5(#hash-range_conditions). Range Conditions
 
 The good thing about this is that we can pass in a range for our fields without it generating a large query as shown in the preamble of this section.
@@ -539,7 +541,9 @@ And this will give you a single +Order+ object for each date where there are ord
 The SQL that would be executed would be something like this:
 
 <sql>
-SELECT date(created_at) as ordered_date, sum(price) as total_price FROM orders GROUP BY date(created_at)
+SELECT date(created_at) as ordered_date, sum(price) as total_price 
+FROM orders 
+GROUP BY date(created_at)
 </sql>
 
 h3. Having
@@ -555,7 +559,10 @@ Order.select("date(created_at) as ordered_date, sum(price) as total_price").grou
 The SQL that would be executed would be something like this:
 
 <sql>
-SELECT date(created_at) as ordered_date, sum(price) as total_price FROM orders GROUP BY date(created_at) HAVING sum(price) > 100
+SELECT date(created_at) as ordered_date, sum(price) as total_price 
+FROM orders 
+GROUP BY date(created_at) 
+HAVING sum(price) > 100
 </sql>
 
 This will return single order objects for each day, but only those that are ordered more than $100 in a day.
@@ -695,7 +702,7 @@ Optimistic locking allows multiple users to access the same record for edits, an
 
 <strong>Optimistic locking column</strong>
 
-In order to use optimistic locking, the table needs to have a column called +lock_version+. Each time the record is updated, Active Record increments the +lock_version+ column. If an update request is made with a lower value in the +lock_version+ field than is currently in the +lock_version+ column in the database, the update request will fail with an +ActiveRecord::StaleObjectError+. Example:
+In order to use optimistic locking, the table needs to have a column called +lock_version+ of type integer. Each time the record is updated, Active Record increments the +lock_version+ column. If an update request is made with a lower value in the +lock_version+ field than is currently in the +lock_version+ column in the database, the update request will fail with an +ActiveRecord::StaleObjectError+. Example:
 
 <ruby>
 c1 = Client.find(1)
@@ -829,7 +836,7 @@ SELECT categories.* FROM categories
   INNER JOIN posts ON posts.category_id = categories.id
 </sql>
 
-Or, in English: "return a Category object for all categories with posts". Note that you will see duplicate categories if more than one post has the same category. If you want unique categories, you can use Category.joins(:post).select("distinct(categories.id)").
+Or, in English: "return a Category object for all categories with posts". Note that you will see duplicate categories if more than one post has the same category. If you want unique categories, you can use Category.joins(:posts).select("distinct(categories.id)").
 
 h5. Joining Multiple Associations
 
@@ -1004,7 +1011,7 @@ Scopes are also chainable within scopes:
 <ruby>
 class Post < ActiveRecord::Base
   scope :published,               -> { where(:published => true) }
-  scope :published_and_commented, -> { published.and(self.arel_table[:comments_count].gt(0)) }
+  scope :published_and_commented, -> { published.where("comments_count > 0") }
 end
 </ruby>