Python MySQL 更新记录



  • 更新记录

    您可以使用“UPDATE”语句来更新表中的现有记录:
    将地址列从“Valley 345”覆盖为“Canyoun 123”:
    import mysql.connector
    
    mydb = mysql.connector.connect(
      host="localhost",
      user="yourusername",
      passwd="yourpassword",
      database="mydatabase"
    )
    
    mycursor = mydb.cursor()
    
    sql = "UPDATE customers SET address = 'Canyon 123' WHERE address = 'Valley 345'"
    
    mycursor.execute(sql)
    
    mydb.commit()
    
    print(mycursor.rowcount, "record(s) affected")
    
    
    重要提示!:请注意以下声明: mydb.commit()。需要进行更改,否则将不对表进行任何更改。
    请注意UPDATE语法中的WHERE子句: WHERE子句指定应更新的记录。如果省略WHERE子句,所有记录将被更新!
  • 防止SQL注入

    通过使用%s占位符方法转义值:
    import mysql.connector
    
    mydb = mysql.connector.connect(
      host="localhost",
      user="yourusername",
      passwd="yourpassword",
      database="mydatabase"
    )
    
    mycursor = mydb.cursor()
    
    sql = "UPDATE customers SET address = %s WHERE address = %s"
    val = ("Valley 345", "Canyon 123")
    
    mycursor.execute(sql, val)
    
    mydb.commit()
    
    print(mycursor.rowcount, "record(s) affected")