Python SQL-从对应值与另一个Select语句的结果匹配的表中选择值

由于标题相当混乱，请允许我澄清。在本例中，我尝试选择10年级学生的所有家长电子邮件。但是，学生的年级存储在另一个表中，这使得select语句相当棘手

这是我迄今为止的尝试，我希望它突出了我所处的障碍

conn = sqlite3.connect('test.db')
c = conn.cursor()

# Makes tables
c.execute(
    """
    CREATE TABLE IF NOT EXISTS student (
        year INTEGER,
        code INTEGER,
        PRIMARY KEY (code)
    )
""")

c.execute(
    """
    CREATE TABLE IF NOT EXISTS studentcontact (
        contactcode INTEGER,
        studentcode INTEGER,
        parentemail TEXT,
        PRIMARY KEY (contactcode),
        FOREIGN KEY (studentcode) REFERENCES student(code)
    )
""")

c.execute("""
    INSERT OR REPLACE INTO student (code, year) VALUES 
        (501, 9), 
        (502, 10), 
        (503, 10)
""")

c.execute("""
    INSERT OR REPLACE INTO studentcontact (contactcode, studentcode, parentemail) VALUES
        (401, 501, "bobjones@email.com"),
        (402, 502, "billwilliams@email.com"),
        (403, 503, "sallydavidson@email.com")
""")

### -- QUERY HERE -- ##

# My attempt so far
query = """
    SELECT code FROM student WHERE year ='10'
    SELECT parentemail FROM studentcontact WHERE studentcode = *results from select statement above*
    """

---

如果我理解正确，您只想加入：

SELECT sc.parentemail
FROM student s JOIN
     studentcontact sc 
     ON s.code = sc.studentcode 
WHERE s.year = 10

一种方法是：

SELECT parentemail
FROM studentcontact
WHERE studentcode IN (
    SELECT code
    FROM student
    WHERE year='10'
)