PHP MYSQL Select statement

the sql for picking the email will need quotes around it, where as the subscriber where clause does not as its an integer

$query = "SELECT * FROM dada_subscribers WHERE subscriber_id={$_GET['subscriber_id']} AND email='{$_GET['email']}' ;";

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not sure with PHP - do you use \" to escape the " character?

$query = "SELECT * FROM dada_subscribers WHERE subscriber_id={$_GET['subscriber_id']} AND email=\"{$_GET['email']}\";";

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I like to end my sql with a ; too.

This might be simpler to understand and read and solves the apostrophe problem.

$query = "SELECT * FROM dada_subscribers WHERE subscriber_id='" . $_GET['subscriber_id'] . "' AND email='" . $_GET['email'] . "'";

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First, that's a very good step you are taking, by recognizing that vulnerability that anyone could put any ID in.

However, that is VERY insecure code. Never, EVER use the value of a $_GET or $_POST or any user-provided variable in a query without cleaning it first. If you make that code live, you could give hackers a way to permanently delete all of the records in that database (not kidding). All they have to do is create an "email address" that has SQL code in it and you're screwed.

This:
$query = "SELECT * FROM dada_subscribers WHERE subscriber_id={$_GET['subscriber_id']} AND email={$_GET['email']}";

Should look like:
$query = "SELECT * FROM dada_subscribers WHERE subscriber_id=" . intval($_GET['subscriber_id']) . " AND email='" . mysql_real_escape_string($_GET['email']) . "'";

What if the person used an easily-accessible tool like Firebug to change their email address in the form (nothing is ever read-only in a web page unless you restrict it on the database permission level)?

Imagine that they change it from:
joe.smith@gmail.com

to:
'; DELETE FROM dada_subscribers; SELECT '

Your query might end up looking like this:
SELECT * FROM dada_subscribers WHERE subscriber_id=123 AND email=''; DELETE FROM dada_subscribers; SELECT '';

Suddenly, anyone has access to run their own database queries on your database and that above one would delete your records.

It's extremely important to be careful with your database queries. Anytime a database query has a variable in it that is coming from a user, make SURE that you're escaping it!

Hi gr8gonzo,

I've carried out your test and attempted to hack the database without success. Thanks for that tip.

I've implemented your solution but a problem has arisen. Once I use the combined subscriber_id and the email in the URL I am able to retrieve the record.

However, if I omit the email address or use an incorrect email address it is not throwing me the error message any longer ("No subscriber record was located").

How do I correct that?

Terry

Terry,

When you report that an SQL query doesn't work, please share the query string with us.

One way to see the string is
echo $query . "<br />"

Of course, you want to remove the echo statement from production software.

Thanks,
Hugh

Hi Hugh,

There was no error message and there should have been. I said that in my post. It returns a blank data form.

Terry

Subscriber is a Number so subscriber = 555 should work

try to change the email format
in regular sql it is a text so it needs single quotes around it
email=johndoe@hotmail.com will not work, you must pass through the quotes to the sql

email='johndoe@hotmail.com'

php should let it slide but perhaps you have a freak version which needs this change

$query = "SELECT * FROM dada_subscribers WHERE subscriber_id={$_GET['subscriber_id']} AND email='{$_GET['email']}'";

Terry,

I understand there's no error message.  I get that.  Happens to me more often than I want to admit.

Print the query string to see what it says.  My guess is that it says something different than what you intend.  (At least that's what happens to me more often than I want to admit.)

What do you mean by blank data form?  Do you mean it's empty or do you mean the page has no text?  If "no text" then I suggest you look in your log file (error_log, probably) to see what went wrong.  PHP syntax errors end up in my error_log file.  If you can't get to the log file, you could run your script through PHP at the command line.  That may or may not work depending on what you have in your script.

Hugh

Hi Hugh,

I printed the query string and it is exactly as it was taken from the URL. Nothing untoward.

Basically, it calls for a record with a unique subscriber_id and the email address that's in the record. When these are correct it returns the record with editable fields (a data entry form).

When I try the subscriber_id with an incorrect email -- according to my code -- it should return an error message. However, it is a returning a blank data form.

Have a look at the code which I attached.

Terry

have you tried splitting the page to

if exists then return <form stuff>
else echo "<br>the records dont match"

Hi esskayb2d,

Yes, the page is structured like that.

Terry

Hello everyone,

Unfortunately, none of the above solutions are doing the job for me and I am going to close this question.

how about pasting your code?

I have pasted AND attached the code, if you go back to my original post.

you pasted two lines of code, and the error


it will be easier if you attach the file so that the professionals here can look at it closer

so do you want it to be an OR not an AND?

if they provide either subid or email you want it to find the records?

Hi gr8gonzo,

Your solution works when using mysql_fetch_array rather than mysql_fetch_assoc.

Thanks
Terry

This solution works when using mysql_fetch_array rather than mysql_fetch_assoc.