r4644@asus: jeremy | 2006-06-16 14:57:03 -0700

 locking
 r4645@asus:  jeremy | 2006-06-17 12:41:30 -0700
 missing reply fixture
 r4646@asus:  jeremy | 2006-06-19 13:05:23 -0700
 Use a per-thread (rather than global) transaction mutex so you may execute concurrent transactions on separate connections.
 r4647@asus:  jeremy | 2006-06-19 13:07:23 -0700
 PostgreSQL: introduce allow_concurrency option which determines whether to use blocking or asynchronous #execute. Adapters with blocking #execute will deadlock Ruby threads. The default value is ActiveRecord::Base.allow_concurrency.
 r4648@asus:  jeremy | 2006-06-19 13:08:40 -0700
 Pass the default allow_concurrency when instantiating new connections.
 r4649@asus:  jeremy | 2006-06-19 13:11:12 -0700
 Break out concurrent transaction tests and run them for PostgreSQLAdapter only (need to fork or system('some_test_script') for the other adapters)
 r4650@asus:  jeremy | 2006-06-19 13:42:48 -0700
 Row locking. Provide a locking clause with the :lock finder option or true for the default "FOR UPDATE".
 r4661@asus:  jeremy | 2006-06-19 15:36:51 -0700
 excise the junk mutex


git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@4460 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

1 files changed, 11 insertions, 0 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
index c45454eacc..d91b919116 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
@@ -91,6 +91,17 @@ module ActiveRecord
         end
       end
 
+      # Appends a locking clause to a SQL statement. *Modifies the +sql+ parameter*.
+      #   # SELECT * FROM suppliers FOR UPDATE
+      #   add_lock! 'SELECT * FROM suppliers', :lock => true
+      #   add_lock! 'SELECT * FROM suppliers', :lock => ' FOR UPDATE'
+      def add_lock!(sql, options)
+        case lock = options[:lock]
+          when true:   sql << ' FOR UPDATE'
+          when String: sql << " #{lock}"
+        end
+      end
+
       def default_sequence_name(table, column)
         nil
       end