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

How many papers were written on Multiuser Receiver in the Decision Feedback this year ?
SELECT DISTINCT paper.paperid FROM keyphrase, paper, paperkeyphrase WHERE keyphrase.keyphrasename = 'Multiuser Receiver in the Decision Feedback' AND paperkeyphrase.keyphraseid = keyphrase.keyphraseid AND paper.paperid = paperkeyphrase.paperid AND paper.year = 2016 GROUP BY paper.paperid HAVING COUNT(DISTINCT keyphrase.keyphrasename) > 1
SELECT DISTINCT "paper"."paperid" FROM "keyphrase" JOIN "paperkeyphrase" ON "keyphrase"."keyphraseid" = "paperkeyphrase"."keyphraseid" JOIN "paper" ON "paper"."paperid" = "paperkeyphrase"."paperid" AND "paper"."year" = 2016 WHERE "keyphrase"."keyphrasename" = 'Multiuser Receiver in the Decision Feedback' GROUP BY "paper"."paperid" HAVING COUNT(DISTINCT "keyphrase"."keyphrasename") > 1