一行Python和SQLite代码，为什么要放“，"? [英] A line of Python and SQLite code, why I need to put ","?

问题描述

c.execute("INSERT INTO numbers VALUES(?)", (random.randint(0,100),))

如果我把上面的代码改成:

If I change the above code, to:

c.execute("INSERT INTO numbers VALUES(?)", (random.randint(0,100)))

我会得到ValueError: parameters are unsupported type.

我不明白为什么我需要放置一个,?有什么区别?

I don't understand why I need the put a ,? What's the difference?

谢谢！

推荐答案

这只是基本的 Python 语法.c.execute() 接受的第二个值是一个元组，当您只向其中放入一个变量时，其语法需要尾随逗号 ,.

It's just basic Python syntax. The second value that c.execute() takes in is a tuple whose syntax requires trailing comma , when you put in just one variable to it.

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