http://reply.papertrans.cn/3/280/27959/27959-21.png
Submitted on: 27 June 1998.
Revised on: 01 August 1998.
Accepted on: 29 August 1998.
SIGMOD RECORD
http://reply.papertrans.cn/3/280/27959/27959-23.png
http://reply.papertrans.cn/3/280/27959/27959-24.png
http://reply.papertrans.cn/3/280/27959/27959-25.png
http://reply.papertrans.cn/3/280/27959/27959-26.png
Submitted on: 06 April 2008.
Revised on: 07 May 2008.
Accepted on: 24 May 2008.
SIGMOD RECORD
Submitted on: 18 May 2012.
Revised on: 14 June 2012.
Accepted on: 30 June 2012.
SIGMOD RECORD---ASSOC COMPUTING MACHINERY
http://reply.papertrans.cn/3/280/27959/27959-29.png
http://reply.papertrans.cn/3/280/27959/27959-30.png