Python operates on sqlite3 to quickly and safely insert an instance of data (anti injection)

The table is created by using the following statement:

create table userinfo(name text, email text)

Faster insertion of data

Time it here with time.clock() to see how fast the three methods work.

import sqlite3
import time
def create_tables(dbname):  
    conn = sqlite3.connect(dbname)
    cursor = conn.cursor()
    cursor.execute('''create table userinfo(name text, email text)''')
    conn.commit()
    cursor.close()
    conn.close()
def drop_tables(dbname):
    conn = sqlite3.connect(dbname)
    cursor = conn.cursor()
    cursor.execute('''drop table userinfo''')
    conn.commit()
    cursor.close()
    conn.close()
def insert1():
    users = [('qq','qq@example.com'),
            ('ww','ww@example.com'),
            ('ee','ee@example.com'),
            ('rr','rr@example.com'),
            ('tt','tt@example.com'),
            ('yy','yy@example.com'),
            ('uu','uu@example.com')
            ]
    start = time.clock()
    conn = sqlite3.connect(dbname)
    cursor = conn.cursor()
    for user in users:
        cursor.execute("insert into userinfo(name, email) values(?, ?)", user)
        conn.commit()
    cursor.close()
    conn.close()
    end = time.clock()
    print start, end, end-start
def insert2():
    users = [('qq','qq@example.com'),
            ('ww','ww@example.com'),
            ('ee','ee@example.com'),
            ('rr','rr@example.com'),
            ('tt','tt@example.com'),
            ('yy','yy@example.com'),
            ('uu','uu@example.com')
            ]
    start = time.clock()
    conn = sqlite3.connect(dbname)
    cursor = conn.cursor()
    for user in users:
        cursor.execute("insert into userinfo(name, email) values(?, ?)", user)
    conn.commit()
    cursor.close()
    conn.close()
    end = time.clock()
    print start, end, end-start
def insert3():
    users = [('qq','qq@example.com'),
            ('ww','ww@example.com'),
            ('ee','ee@example.com'),
            ('rr','rr@example.com'),
            ('tt','tt@example.com'),
            ('yy','yy@example.com'),
            ('uu','uu@example.com')
            ]
    start = time.clock()
    conn = sqlite3.connect(dbname)
    cursor = conn.cursor()
    cursor.executemany("insert into userinfo(name, email) values(?, ?)", users)
    conn.commit()
    cursor.close()
    conn.close()
    end = time.clock()
    print start, end, end-start
if __name__ == '__main__':
    dbname = 'test.db'
    create_tables(dbname)
    insert1()
    drop_tables(dbname)
    create_tables(dbname)
    insert2()
    drop_tables(dbname)
    create_tables(dbname)
    insert3()
    drop_tables(dbname)

Results of a certain operation:

4.05223164501e-07 0.531585119557 0.531584714334
0.755963264089 0.867329935942 0.111366671854
1.0324360882 1.12175173111 0.0893156429109

Another running result:

4.05223164501e-07 0.565988971446 0.565988566223
0.768132520942 0.843723660494 0.0755911395524
1.04367819446 1.13247636739 0.0887981729298

In the run result, the third column represents the time taken to insert the data. Taken together, the method insert1() is slow because each insert commits ().

More secure database operations

Code first:

import sqlite3
def create_tables(dbname):  
    conn = sqlite3.connect(dbname)
    cursor = conn.cursor()
    cursor.execute('''create table userinfo(name text, email text)''')
    conn.commit()
    cursor.close()
    conn.close()
def drop_tables(dbname):
    conn = sqlite3.connect(dbname)
    cursor = conn.cursor()
    cursor.execute('''drop table userinfo''')
    conn.commit()
    cursor.close()
    conn.close()
def insert():
    users = [('qq','qq@example.com'),
            ('ww','ww@example.com'),
            ('ee','ee@example.com'),
            ('rr','rr@example.com'),
            ('tt','tt@example.com'),
            ('yy','yy@example.com'),
            ('uu','uu@example.com')
            ]
    conn = sqlite3.connect(dbname)
    cursor = conn.cursor()
    cursor.executemany("insert into userinfo(name, email) values(?, ?)", users)
    conn.commit()
    cursor.close()
    conn.close()
def insecure_select(text):
    conn = sqlite3.connect(dbname)
    cursor = conn.cursor()
    print "select name from userinfo where email='%s'" % text
    for row in cursor.execute("select name from userinfo where email='%s'" % text):
        print row
def secure_select(text):
    conn = sqlite3.connect(dbname)
    cursor = conn.cursor()
    print "select name from userinfo where email='%s'" % text
    for row in cursor.execute("select name from userinfo where email= ? ", (text,)):
        print row
if __name__ == '__main__':
    dbname = 'test.db'
    create_tables(dbname)
    insert()
    insecure_select("uu@example.com")
    insecure_select("' or 1=1;--")
    secure_select("uu@example.com")
    secure_select("' or 1=1;--")
    drop_tables(dbname)

Operation results:

select name from userinfo where email='uu@example.com'
(u'uu',)
select name from userinfo where email='' or 1=1;--'
(u'qq',)
(u'ww',)
(u'ee',)
(u'rr',)
(u'tt',)
(u'yy',)
(u'uu',)
select name from userinfo where email='uu@example.com'
(u'uu',)
select name from userinfo where email='' or 1=1;--'

The functions insecure_select(text) and secure_select(text) are meant to get the corresponding username information based on the email. But the implementation of insecure_select(text) is prone to SQL injection.

Insecure_select (" 'or 1 = 1; "--") is an example. In insecure_select(), cursor. Execute () takes only one parameter, the SQL statement, and the generated SQL statement executes as usual if there is a problem.

The implementation of secure_select(text) prevents SQL injection, and the first argument of cursor. Execute () USES a placeholder? The second parameter specifies the value for each placeholder, which (at the very least) escapes special characters on the underlying implementation to prevent SQL injection.