Můžete použít DISTINCT
:
SELECT DISTINCT studid FROM registration WHERE courseid IN ('100', 101');
nebo GROUP BY
:
SELECT studid FROM registration WHERE courseid IN ('100', '101') GROUP BY studid;
Můžete použít DISTINCT
:
SELECT DISTINCT studid FROM registration WHERE courseid IN ('100', 101');
nebo GROUP BY
:
SELECT studid FROM registration WHERE courseid IN ('100', '101') GROUP BY studid;