SQLite 3.27

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CREATE TABLE employees (`id` TEXT);
INSERT INTO employees (`id`) VALUES
  ('e01'), ('e02'), ('e03'), ('e04');
CREATE TABLE vacation (`eid` VARCHAR(3), `departid` VARCHAR(12), `quarter` VARCHAR(6), `year` INTEGER);
INSERT INTO vacation (`eid`, `departid`, `quarter`, `year`) VALUES
  ('e04', 'marketing01', 'Winter', '2010'),
  ('e01', 'theboard00', 'Winter', '2011'),
  ('e01', 'theboard00', 'Spring', '2011'),
  ('e01', 'theboard00', 'Fall', '2010'),
  ('e02', 'enginering01', 'Fall', '2008'),
  ('e03', 'marketing01', 'Spring', '2009');
SELECT v1.eid
FROM vacation v1 INNER JOIN vacation v2
ON v1.year = v2.year - 1
WHERE v1.quarter = 'Fall' AND v1.quarter <> v2.quarter
GROUP BY v1.eid
HAVING COUNT(*) = 2


eid


e01


SELECT * FROM employees
WHERE id IN (
  SELECT v1.eid
  FROM vacation v1 INNER JOIN vacation v2
  ON v1.year = v2.year - 1
  WHERE v1.quarter = 'Fall' AND v1.quarter <> v2.quarter
  GROUP BY v1.eid
  HAVING COUNT(*) = 2
)


id


e01