diff --git a/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
index d645376cb2432..e7f7b37b277aa 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
@@ -276,7 +276,7 @@ def select_rows(sql, name = nil)
         rows = []
         result.each { |row| rows << row }
         result.free
-        @connection.more_results && @connection.next_result    # invoking stored procedures with CLIENT_MULTI_RESULTS requires this to tidy up else connection will be dropped 
+        @connection.more_results && @connection.next_result    # invoking stored procedures with CLIENT_MULTI_RESULTS requires this to tidy up else connection will be dropped
         rows
       end
 
@@ -358,10 +358,10 @@ def structure_dump #:nodoc:
           sql = "SHOW TABLES"
         end
 
-        select_all(sql).inject("") do |structure, table|
+        select_all(sql).map do |table|
           table.delete('Table_type')
-          structure += select_one("SHOW CREATE TABLE #{quote_table_name(table.to_a.first.last)}")["Create Table"] + ";\n\n"
-        end
+          select_one("SHOW CREATE TABLE #{quote_table_name(table.to_a.first.last)}")["Create Table"] + ";\n\n"
+        end.join("")
       end
 
       def recreate_database(name, options = {}) #:nodoc:
@@ -620,7 +620,7 @@ def select(sql, name = nil)
           rows = []
           result.each_hash { |row| rows << row }
           result.free
-          @connection.more_results && @connection.next_result    # invoking stored procedures with CLIENT_MULTI_RESULTS requires this to tidy up else connection will be dropped 
+          @connection.more_results && @connection.next_result    # invoking stored procedures with CLIENT_MULTI_RESULTS requires this to tidy up else connection will be dropped
           rows
         end