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

keyphrases used by Kaiming He
SELECT DISTINCT keyphrase.keyphraseid FROM author, keyphrase, paper, paperkeyphrase, writes WHERE author.authorname = 'Kaiming He' AND paperkeyphrase.keyphraseid = keyphrase.keyphraseid AND paper.paperid = paperkeyphrase.paperid AND writes.authorid = author.authorid AND writes.paperid = paper.paperid
SELECT DISTINCT "keyphrase"."keyphraseid" FROM "author" JOIN "writes" ON "author"."authorid" = "writes"."authorid" JOIN "paper" ON "paper"."paperid" = "writes"."paperid" JOIN "paperkeyphrase" ON "paper"."paperid" = "paperkeyphrase"."paperid" JOIN "keyphrase" ON "keyphrase"."keyphraseid" = "paperkeyphrase"."keyphraseid" WHERE "author"."authorname" = 'Kaiming He'