diff options
Diffstat (limited to 'activerecord/lib/active_record/relation/query_methods.rb')
| -rw-r--r-- | activerecord/lib/active_record/relation/query_methods.rb | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/activerecord/lib/active_record/relation/query_methods.rb b/activerecord/lib/active_record/relation/query_methods.rb index 6f0f2125dc..b0535cfff5 100644 --- a/activerecord/lib/active_record/relation/query_methods.rb +++ b/activerecord/lib/active_record/relation/query_methods.rb @@ -100,7 +100,7 @@ module ActiveRecord # # === conditions # - # If you want to add conditions to your included models you'll have + # If you want to add string conditions to your included models, you'll have # to explicitly reference them. For example: # # User.includes(:posts).where('posts.name = ?', 'example') @@ -111,6 +111,12 @@ module ActiveRecord # # Note that #includes works with association names while #references needs # the actual table name. + # + # If you pass the conditions via hash, you don't need to call #references + # explicitly, as #where references the tables for you. For example, this + # will work correctly: + # + # User.includes(:posts).where(posts: { name: 'example' }) def includes(*args) check_if_method_has_arguments!(:includes, args) spawn.includes!(*args) @@ -154,6 +160,19 @@ module ActiveRecord self end + # Extracts a named +association+ from the relation. The named association is first preloaded, + # then the individual association records are collected from the relation. Like so: + # + # account.memberships.extract_associated(:user) + # # => Returns collection of User records + # + # This is short-hand for: + # + # account.memberships.preload(:user).collect(&:user) + def extract_associated(association) + preload(association).collect(&association) + end + # Use to indicate that the given +table_names+ are referenced by an SQL string, # and should therefore be JOINed in any query rather than loaded separately. # This method only works in conjunction with #includes. |