我们知道Python3.x引入了新的字符串格式化语法。不同于Python2.x的
代码如下:
"%s %s "%(a,b)
Python3.x是
代码如下:
"{0} {1}".format(a,b)
今天我在用MySQLdb时，需要用带参数的
代码如下:
cursor.execute(sql,param)
语句来完成SQL操作。被其他文章的陈旧说法给误导，用了
代码如下:
cursor.execute('insert into test values(%s,%s,%s)',param)
其中param是一个元组，表示要插入的数据，元组中的各个元素即是数据库中各列的值。
但是执行起来总是会抛出数据库异常，错误信息：
代码如下:
【1064】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'(%s,%s,%s)'at line……（以下省略）。
其实只要改成这样就好：
代码如下:
cursor.execute('insert into test values({0},{1},{2})',param)
实话说，Python3为了填上Python2的各坑导致了不向下兼容，使得学习Python3的成本提高了不少。但是为了不阻碍科技发展、社会进步，我还是毅然决然投身新版本……
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