http://www.thinkit.co.jp/free/article/0606/16/4/
http://www.microsoft.com/japan/sql/prodinfo/previousversions/select/points2.mspx
http://msdn.microsoft.com/ja-jp/library/ms179530(SQL.90).aspx
http://www.atmarkit.co.jp/fwin2k/hawin/sql02/sql02_01.html