CREATE TABLE paperdataset (paperid NUMBER, datasetid NUMBER)
CREATE TABLE field (fieldid NUMBER)
CREATE TABLE paperkeyphrase (paperid NUMBER, keyphraseid NUMBER)
CREATE TABLE dataset (datasetid NUMBER, datasetname VARCHAR2)
CREATE TABLE paperfield (fieldid NUMBER, paperid NUMBER)
CREATE TABLE keyphrase (keyphraseid NUMBER, keyphrasename VARCHAR2)
CREATE TABLE writes (paperid NUMBER, authorid NUMBER)
CREATE TABLE journal (journalid NUMBER, journalname VARCHAR2)
CREATE TABLE venue (venueid NUMBER, venuename VARCHAR2)
CREATE TABLE author (authorid NUMBER, authorname VARCHAR2)
CREATE TABLE paper (paperid NUMBER, title VARCHAR2, venueid NUMBER, year NUMBER, numciting NUMBER, numcitedby NUMBER, journalid NUMBER)
CREATE TABLE cite (citingpaperid NUMBER, citedpaperid NUMBER)

who does chasins collaborate with ?
SELECT DISTINCT AUTHOR_1.authorid FROM author AS AUTHOR_0, author AS AUTHOR_1, writes AS WRITES_0, writes AS WRITES_1 WHERE AUTHOR_0.authorname = 'chasins' AND WRITES_0.authorid = AUTHOR_0.authorid AND WRITES_1.authorid = AUTHOR_1.authorid AND WRITES_1.paperid = WRITES_0.paperid
SELECT DISTINCT "AUTHOR_1"."authorid" FROM "author" "AUTHOR_0" JOIN "writes" "WRITES_0" ON "AUTHOR_0"."authorid" = "WRITES_0"."authorid" JOIN "writes" "WRITES_1" ON "WRITES_0"."paperid" = "WRITES_1"."paperid" JOIN "author" "AUTHOR_1" ON "AUTHOR_1"."authorid" = "WRITES_1"."authorid" WHERE "AUTHOR_0"."authorname" = 'chasins'