CREATE TABLE paperkeyphrase (paperid INT, keyphraseid INT)
CREATE TABLE author (authorid INT, authorname VARCHAR)
CREATE TABLE dataset (datasetid INT, datasetname VARCHAR)
CREATE TABLE cite (citingpaperid INT, citedpaperid INT)
CREATE TABLE journal (journalid INT, journalname VARCHAR)
CREATE TABLE venue (venueid INT, venuename VARCHAR)
CREATE TABLE field (fieldid INT)
CREATE TABLE paper (paperid INT, title VARCHAR, venueid INT, year INT, numciting INT, numcitedby INT, journalid INT)
CREATE TABLE paperdataset (paperid INT, datasetid INT)
CREATE TABLE paperfield (fieldid INT, paperid INT)
CREATE TABLE keyphrase (keyphraseid INT, keyphrasename VARCHAR)
CREATE TABLE writes (paperid INT, authorid INT)

who published the most papers at EMNLP or ACL since 2011
SELECT DISTINCT COUNT(DISTINCT paper.paperid), writes.authorid FROM keyphrase, paper, paperkeyphrase, venue, writes WHERE paperkeyphrase.keyphraseid = keyphrase.keyphraseid AND paper.paperid = paperkeyphrase.paperid AND paper.year > 2011 AND venue.venueid = paper.venueid AND venue.venuename IN ('ACL', 'EMNLP') AND writes.paperid = paper.paperid GROUP BY writes.authorid ORDER BY COUNT(paper.paperid) DESC
SELECT DISTINCT COUNT(DISTINCT "paper"."paperid"), "writes"."authorid" FROM "keyphrase" JOIN "paperkeyphrase" ON "keyphrase"."keyphraseid" = "paperkeyphrase"."keyphraseid" JOIN "paper" ON "paper"."paperid" = "paperkeyphrase"."paperid" AND "paper"."year" > 2011 JOIN "venue" ON "paper"."venueid" = "venue"."venueid" AND "venue"."venuename" IN ('ACL', 'EMNLP') JOIN "writes" ON "paper"."paperid" = "writes"."paperid" GROUP BY "writes"."authorid" ORDER BY COUNT("paper"."paperid") DESC NULLS LAST