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

How many papers has luke zettlemoyer published ?
SELECT DISTINCT COUNT(DISTINCT writes.paperid) FROM author, writes WHERE author.authorname = 'luke zettlemoyer' AND writes.authorid = author.authorid
SELECT DISTINCT COUNT(DISTINCT "writes"."paperid") FROM "author" JOIN "writes" ON "author"."authorid" = "writes"."authorid" WHERE "author"."authorname" = 'luke zettlemoyer'