1 files changed, 25 insertions, 5 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
index 64070f0e6c..fc60c4c00d 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
@@ -1,4 +1,5 @@
 require 'active_record/connection_adapters/abstract_adapter'
+require 'active_record/connection_adapters/statement_pool'
 require 'active_record/connection_adapters/mysql/column'
 require 'active_record/connection_adapters/mysql/explain_pretty_printer'
 require 'active_record/connection_adapters/mysql/quoting'
@@ -56,9 +57,19 @@ module ActiveRecord
       INDEX_TYPES  = [:fulltext, :spatial]
       INDEX_USINGS = [:btree, :hash]
 
+      class StatementPool < ConnectionAdapters::StatementPool
+        private
+
+        def dealloc(stmt)
+          stmt[:stmt].close
+        end
+      end
+
       def initialize(connection, logger, connection_options, config)
         super(connection, logger, config)
 
+        @statements = StatementPool.new(self.class.type_cast_config_to_integer(config.fetch(:statement_limit) { 1000 }))
+
         if version < '5.0.0'
           raise "Your version of MySQL (#{full_version.match(/^\d+\.\d+\.\d+/)[0]}) is too old. Active Record supports MySQL >= 5.0."
         end
@@ -93,6 +104,12 @@ module ActiveRecord
         true
       end
 
+      # Returns true, since this connection adapter supports prepared statement
+      # caching.
+      def supports_statement_cache?
+        true
+      end
+
       # Technically MySQL allows to create indexes with the sort order syntax
       # but at the moment (5.5) it doesn't yet implement them
       def supports_index_sort_order?
@@ -178,6 +195,14 @@ module ActiveRecord
         end
       end
 
+      # CONNECTION MANAGEMENT ====================================
+
+      # Clears the prepared statements cache.
+      def clear_cache!
+        reload_type_map
+        @statements.clear
+      end
+
       #--
       # DATABASE STATEMENTS ======================================
       #++
@@ -191,11 +216,6 @@ module ActiveRecord
         MySQL::ExplainPrettyPrinter.new.pp(result, elapsed)
       end
 
-      def clear_cache!
-        super
-        reload_type_map
-      end
-
       # Executes the SQL statement in the context of this connection.
       def execute(sql, name = nil)
         log(sql, name) { @connection.query(sql) }