如何获得带有外键的表的倍数值？

Question

如何让一个老师的所有学生，每个学生只有一个老师，每个老师有很多学生，我正在使用这个SQL请求，它只给每个老师带来一个学生，你能帮我吗？

   $data = '';
          $sth = Model::connect()->prepare('SELECT a.name ,
          b.nameTeacher 
          FROM table1 b , table2 a
         WHERE a.id_teacher = b.id GROUP BY b.id');
               $sth->execute();
                 $data = $sth->fetchAll();


        return $data;

表1

教师： Id nameTeacher

表2

学生： Id 名字 Id_teacher

Answer 1

删除GROUP BY并学习使用正确、显式、标准的 JOIN语法：

SELECT a.name, b.nameTeacher 
FROM table1 b JOIN
     table2 a
     ON a.id_teacher = b.id ;

Answer 2

这将起作用：

select a.name,b.nameTeacher from students a ,teacher b
where a.Id_teacher=b.Id 

Answer 3

SELECT b.nameTeacher, count(a.name) as numberOfStudents
      FROM table1 b , table2 a
     WHERE a.id_teacher = b.id GROUP BY b.id

或者：

 SELECT a.Id, a.name
      FROM table1 b , table2 a
     WHERE a.id_teacher = b.id and (b.id = [input ID] or b.nameTeacher = [input name]