title: congressional samples for approximate answering of group-by queries. authors: viswanath poosala , swarup acharya , phillip b. gibbons. venue: sigmod conference. year: 2000
title: congressional samples for approximate answering of group-by queries. authors: swarup acharya , phillip b. gibbons , viswanath poosala. venue: international conference on management of data. year: 2000