Pyhton中防止SQL注入的方法
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2023-11-28 19:51:40
复制代码 代码如下:
c=db.cursor()
max_price=5
c.execute("""select spam, eggs, sausage from b...
复制代码 代码如下:
c=db.cursor()
max_price=5
c.execute("""select spam, eggs, sausage from breakfast
where price < %s""", (max_price,))
注意，上面的sql字符串与后面的tuple之间的分隔符是逗号，平时拼写sql用的是%。
如果按照以下写法，是容易产生sql注入的：
复制代码 代码如下:
c.execute("""select spam, eggs, sausage from breakfast
where price < %s""" % (max_price,))
这个和php里的pdo是类似的，原理同mysql prepared statements。
python
using the python db api, don't do this:
# do not do it this way.
复制代码 代码如下:
cmd = "update people set name='%s' where id='%s'" % (name, id) curs.execute(cmd)
instead, do this:
复制代码 代码如下:
cmd = "update people set name=%s where id=%s" curs.execute(cmd, (name, id))
note that the placeholder syntax depends on the database you are using.
复制代码 代码如下:
'qmark' question mark style, e.g. '...where name=?' 'numeric' numeric, positional style, e.g. '...where name=:1' 'named' named style, e.g. '...where name=:name' 'format' ansi c printf format codes, e.g. '...where name=%s' 'pyformat' python extended format codes, e.g. '...where name=%(name)s'
the values for the most common databases are:
复制代码 代码如下:
>>> import mysqldb; print mysqldb.paramstyle format >>> import psycopg2; print psycopg2.paramstyle pyformat >>> import sqlite3; print sqlite3.paramstyle qmark
so if you are using mysql or postgresql, use %s (even for numbers and other non-string values!) and if you are using sqlite use ?