Python Sqlite如何使用外键从不同的表中打印数据？

Question

I'm new to sqlite in python and I can't seem to work out why the foreign key isn't working? What do I need to do? I want to print details from a different table! help!

c.execute("PRAGMA foreign_keys = ON")

c.execute('''CREATE TABLE IF NOT EXISTS Staff
(staff_id integer UNIQUE,
staff_name text,
staff_DOB date,
staff_gender text,
Primary Key(staff_id)
)
''')

c.execute('''CREATE TABLE IF NOT EXISTS Clients
(client_id integer UNIQUE,
client_name text,
client_DOB date,
client_gender text,
staff integer,
Primary Key(client_id),
FOREIGN KEY(staff) REFERENCES Staff(staff_id)
)
''')

c.execute('''INSERT INTO Staff (staff_name,staff_DOB,staff_gender) VALUES ("joe","24/09/1999","male")''')

c.execute('''INSERT INTO Clients (client_name,client_DOB,client_gender, staff) VALUES ("sarah","12/09/2001","female",1)''')

c.execute("SELECT staff_name FROM Clients")
data = c.fetchone()
print(data)

Answer 1

You will need to JOIN the tables by the foreign key.

For example:

SELECT
t1.*,
t2.staff_name
FROM Clients t1
LEFT JOIN Staff t2
ON (t2.id = t1.staff);