Parameterized SQL statements vs. very simple method
- by Philipp G
When I started to write the first SQL-Statements in my programs I felt quite comfortable with protecting myself against SQL-Injection with a very simple method that a colleague showed me. It replaced all single quotes with two single quotes.
So for example there is a searchfield in which you can enter a customername to search in the customertable. If you would enter
Peter's Barbershop
The SELECT Statement would look like
SELECT *
FROM Customers
WHERE Customername = 'Peter''s Barbershop'
If now an attacker would insert this:
';DROP TABLE FOO; --
The statement would look like:
SELECT *
FROM Customers
WHERE Customername = ''';DROP TABLE FOO;--'
It would not drop any table, but search the customertable for the customername ';DROP TABLE FOO;-- which, I suppose, won't be found ;-)
Now after a while of writing statements and protecting myself against SQL-Injection with this method, I read that many developers use parameterized statements, but I never read an article where "our" method was used. So definitely there is a good reason for it.
What scenarios would parameterized statements cover but our method doesn't? What are the advantages of parameterized statements compared to our method?
Thanks
Philipp