Question: What is the last name of the author that has published the most papers?
Schema: create table authorship (authid varchar, paperid varchar, PRIMARY KEY (authid)); create table authors (lname varchar, fname varchar, authid varchar, PRIMARY KEY (lname)); create table papers (paperid varchar, PRIMARY KEY (paperid))
SQL: select t1.lname from authors as t1 join authorship as t2 on t1.authid = t2.authid join papers as t3 on t2.paperid = t3.paperid group by t1.fname, t1.lname order by count(*) desc limit 1