PyMySQL插入NULL或字符串 [英] PyMySQL Insert NULL or a String

问题描述

我试图用PyMySQL插入一个字段(title)，该字段可以是NULL或字符串.但这不起作用.

I tried to insert a field (title) with PyMySQL that can be NULL or a string. But it doesn't work.

query = """
    INSERT INTO `chapter` (title, chapter, volume)
    VALUES ("%s", "%s", %d)
"""

cur.execute(query % (None, "001", 1))
cur.execute(query % ("Title", "001", 1))

此代码将None插入数据库.如果删除第一个%s周围的双引号，则会引发错误:

This code inserts None into the database. If I remove the double quote around the first %s, it throws an error:

pymysql.err.InternalError: (1054, "Unknown column 'None' in 'field list'")

如何插入NULL?

推荐答案

1)切勿对SQL使用字符串格式.

1) Never use string formatting for SQL.

2)尝试以下操作:

query = """
INSERT INTO `chapter` (title, chapter, volume)
VALUES (%s, %s, %s)
"""
cur.execute(query, (None, "001", 1))

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