CREATE TABLE Maintenance_Engineers (engineer_id VARCHAR, first_name VARCHAR, last_name VARCHAR)
CREATE TABLE Engineer_Visits (engineer_id VARCHAR)

Among those engineers who have visited, which engineer makes the least number of visits? List the engineer id, first name and last name.
SELECT T1.engineer_id, T1.first_name, T1.last_name FROM Maintenance_Engineers AS T1 JOIN Engineer_Visits AS T2 ON T1.engineer_id = T2.engineer_id GROUP BY T1.engineer_id ORDER BY COUNT(*) LIMIT 1
SELECT "T1"."engineer_id", "T1"."first_name", "T1"."last_name" FROM "Maintenance_Engineers" AS "T1" JOIN "Engineer_Visits" AS "T2" ON "T1"."engineer_id" = "T2"."engineer_id" GROUP BY "T1"."engineer_id" ORDER BY COUNT(*) NULLS FIRST LIMIT 1