如何在python中使用mysql中带变量的select语句

Question

我想在where子句中使用带变量的select语句。我已经对此进行了研究How to use variables in SQL statement in Python?和Inserting Variables MySQL Using Python, Not Working。香港专业教育学院尝试实施所提供的解决方案，但它无法正错误代码

mysql.connector.errors.ProgrammingError: 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '?' at line 1

下面是代码：

name = input("Write your name")
mycursor.execute("SELECT name FROM workers WHERE symbol=?", name)

我做错了什么？

Answer 1

MySQL库使用%s作为占位符。

mycursor.execute("SELECT name FROM workers WHERE symbol=%s", name)

尽管有相似之处，但这不是字符串替换。

Answer 2

好的Spike7这正是理想的，

mycursor.execute("SELECT name FROM workers WHERE symbol=%s", (name,))  

或

mycursor.execute("SELECT name FROM workers WHERE symbol=?", (name,)) 

the first link you given上接受的答案解释了evertything。

Answer 3

您可以使用

mycursor.execute("SELECT name FROM workers WHERE symbol={}".format(name))

这仅在变量名不是字符串的情况下有效

Answer 4

mycursor.execute("SELECT name FROM workers WHERE symbol=%s"% name)  

那是