CREATE TABLE drivers (driverid VARCHAR2)
CREATE TABLE races (raceid VARCHAR2)
CREATE TABLE results (driverid VARCHAR2, raceid VARCHAR2)

Find the driver id and number of races of all drivers who have at most participated in 30 races?
SELECT T1.driverid, COUNT(*) FROM drivers AS T1 JOIN results AS T2 ON T1.driverid = T2.driverid JOIN races AS T3 ON T2.raceid = T3.raceid GROUP BY T1.driverid HAVING COUNT(*) <= 30
SELECT "T1"."driverid", COUNT(*) FROM "drivers" "T1" JOIN "results" "T2" ON "T1"."driverid" = "T2"."driverid" JOIN "races" "T3" ON "T2"."raceid" = "T3"."raceid" GROUP BY "T1"."driverid" HAVING COUNT(*) <= 30