关于提供的绑定(bind)数量的 Python sqlite3 错误

Question

我确定之前已经有人问过并回答过这个问题，但要么我很愚蠢，要么没有一个答案对我有用。也许我只是不明白。但是，这就是问题所在；我得到了这门课:

import sqlite3

class User:
   def __init__(self, name, age):
        self.name = name
        self.age = age



   def saveToDatabase(self):
        connection = sqlite3.connect("users.db")
        cur = connection.cursor()

        cur.execute("DROP TABLE IF EXISTS users")
        cur.execute("CREATE TABLE users (name TEXT PRIMARY KEY, age INTEGER)")
        cur.execute("INSERT OR REPLACE INTO users VALUES (?,?)", (self.name, self.age))

        connection.commit()
        connection.close()

    @staticmethod
    def printUserFromDatabase(name):
        connection = sqlite3.connect("users.db")
        cur = connection.cursor()

        cur.execute("SELECT * FROM users WHERE name=?", name)
        print(cur.fetchone())

        connection.close()

它起作用了，创建了数据库，我可以向其中添加用户，但是每当我尝试从数据库中打印用户时，就会发生这种情况:

>>> tom = User("Tom", 24)
>>> tom.saveToDatabase()
>>> User.printUserFromDatabase("Tom")
Traceback (most recent call last):
  File "<pyshell#7>", line 1, in <module>
    User.printUserFromDatabase("Tom")
  File "C:\Users\Markus\Desktop\foo\foo.py", line 25, in printUserFromDatabase
    cur.execute("SELECT * FROM users WHERE name=?", name)
sqlite3.ProgrammingError: Incorrect number of bindings supplied. The current statement uses 1, and there are 3 supplied.
>>> 

Answer 1

因为 name 是可迭代的，所以它试图解压它......把它放在一个只有自己修复的元组中

cur.execute("SELECT * FROM users WHERE name=?", (name,))