Question with variable in mysql_query()

Wink-

Alright here is the scenario, I am storing images as blobs in a database. I am retrieving them by their ID which is linked to and the variable comes from the link.
So, for picture 42, the $_GET['id'] echo's 42.

I assign

$id = $_GET['id'];

echoing this gives me the correct number.

Then I try this statement:

$gotten = mysql_query("SELECT `filecontent` FROM `tbl_dmrinfo` WHERE `id` = '$id'");

Which does not correctly retrieve the blob. However,

$gotten = mysql_query("SELECT `filecontent` FROM `tbl_dmrinfo` WHERE `id` = 42");

Works perfectly. So I have to assume I have a problem with my SQL statement.

Any light would be greatly appreciated.

Rob

cahva

Well it should work because the only thing that is different, is the single quotes around $id.
Check that the query is what it seems to be:

$sql = "SELECT `filecontent` FROM `tbl_dmrinfo` WHERE `id` = '$id'";
echo $sql; // print for debug
$gotten = mysql_query($sql);

Hope you are not using $_GET['id'] as is because you should atleast run it through mysql_real_escape_string and make sure its an integer. You can also take off simple quotes around $id. Integers dont need those in sql.

Wink-

I've used

is_int()

to check make sure that $id is an integer. I've echoed the statement

$sql = "SELECT `filecontent` FROM `tbl_dmrinfo` WHERE `id` = $id";
echo $sql;

And I get the line:
SELECT filecontent FROM tbl_dmrinfo WHERE id = 42

I am completely perplexed!

I do not understand why I can substitute

$id=42;
$sql = "SELECT `filecontent` FROM `tbl_dmrinfo` WHERE `id` = $id";

with

$sql = "SELECT `filecontent` FROM `tbl_dmrinfo` WHERE `id` = 42";

and the query works fine. Puzzling!