如何在不选择ORDER BY字段的情况下选择DISTINCT行

如何在不选择ORDER BY字段的情况下选择DISTINCT行

SELECt s.pIDFROM students s JOIN mentors m ON s.pID = m.pID   WHERe m.tags LIKE '%a%'GROUP BY s.pIDORDER BY MAX(s.sID) DESC