Fixed the Broken pipe error on SHOW FIELDs queries too

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@746 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activerecord/lib/active_record/connection_adapters/mysql_adapter.rb

@@ -65,11 +65,8 @@ module ActiveRecord
  
       def columns(table_name, name = nil)
         sql = "SHOW FIELDS FROM #{table_name}" 
-        result = nil
-        log(sql, name, @connection) { |connection| result = connection.query(sql) }
- 
         columns = []
-        result.each { |field| columns << Column.new(field[0], field[4], field[1]) }
+        execute(sql, name).each { |field| columns << Column.new(field[0], field[4], field[1]) }
         columns
       end