CREATE TABLE prereq (course_id VARCHAR, prereq_id VARCHAR)
CREATE TABLE course (title VARCHAR, course_id VARCHAR)

Find the title of course whose prerequisite is course Differential Geometry.
SELECT title FROM course WHERE course_id IN (SELECT T1.course_id FROM prereq AS T1 JOIN course AS T2 ON T1.prereq_id = T2.course_id WHERE T2.title = 'Differential Geometry')
WITH "_u_0" AS (SELECT "T1"."course_id" FROM "prereq" AS "T1" JOIN "course" AS "T2" ON "T1"."prereq_id" = "T2"."course_id" AND "T2"."title" = 'Differential Geometry' GROUP BY "course_id") SELECT "title" FROM "course" LEFT JOIN "_u_0" AS "_u_0" ON "_u_0"."" = "course_id" WHERE NOT "_u_0"."" IS NULL