CREATE TABLE cite (cited INT, citing INT)
CREATE TABLE author (aid INT, homepage VARCHAR, name VARCHAR, oid INT)
CREATE TABLE conference (cid INT, homepage VARCHAR, name VARCHAR)
CREATE TABLE publication_keyword (kid INT, pid INT)
CREATE TABLE publication (abstract VARCHAR, cid INT, citation_num INT, jid INT, pid INT, reference_num INT, title VARCHAR, year INT)
CREATE TABLE writes (aid INT, pid INT)
CREATE TABLE domain_journal (did INT, jid INT)
CREATE TABLE domain_keyword (did INT, kid INT)
CREATE TABLE keyword (keyword VARCHAR, kid INT)
CREATE TABLE journal (homepage VARCHAR, jid INT, name VARCHAR)
CREATE TABLE domain_conference (cid INT, did INT)
CREATE TABLE domain_publication (did INT, pid INT)
CREATE TABLE domain (did INT, name VARCHAR)
CREATE TABLE organization (continent VARCHAR, homepage VARCHAR, name VARCHAR, oid INT)
CREATE TABLE domain_author (aid INT, did INT)

return me the paper with the most citations .
SELECT title FROM publication ORDER BY citation_num DESC LIMIT 1
SELECT "title" FROM "publication" ORDER BY "citation_num" DESC NULLS LAST LIMIT 1