如何在Treeview / Tkinter (SQLite)中从不同的表中获取不同的值？

import tkinter as tk
from tkinter import ttk
import sqlite3

# 创建数据库连接
conn = sqlite3.connect('example.db')
cursor = conn.cursor()

# 创建表
cursor.execute('''CREATE TABLE IF NOT EXISTS users (
                    id INTEGER PRIMARY KEY,
                    name TEXT NOT NULL)''')
cursor.execute('''CREATE TABLE IF NOT EXISTS orders (
                    id INTEGER PRIMARY KEY,
                    user_id INTEGER,
                    product TEXT NOT NULL,
                    FOREIGN KEY(user_id) REFERENCES users(id))''')

# 插入示例数据
cursor.execute("INSERT INTO users (name) VALUES ('Alice')")
cursor.execute("INSERT INTO users (name) VALUES ('Bob')")
cursor.execute("INSERT INTO orders (user_id, product) VALUES (1, 'Book')")
cursor.execute("INSERT INTO orders (user_id, product) VALUES (2, 'Pen')")

conn.commit()

# 创建Tkinter窗口
root = tk.Tk()
root.title("Treeview with SQLite")

# 创建Treeview组件
tree = ttk.Treeview(root, columns=("ID", "Name", "Product"), show="headings")
tree.heading("ID", text="ID")
tree.heading("Name", text="Name")
tree.heading("Product", text="Product")
tree.pack()

# 从不同表中获取数据并插入到Treeview
cursor.execute("SELECT users.id, users.name, orders.product FROM users JOIN orders ON users.id = orders.user_id")
rows = cursor.fetchall()

for row in rows:
    tree.insert("", tk.END, values=row)

# 关闭数据库连接
cursor.close()
conn.close()

root.mainloop()