使用ID的md5版本查询字段

Question

EDITED TO ADD MORE INFO

I need to use mysql's md5 function to select an item using it's id field ( uid ). I have a separate database from my users called recover_db that has an md5 hashed value of the user id in it and a time stamp.

Currently the users visit a link like this:

recover-MD%HASHEDUSERID.html

Then the system takes that MD%HASHEDUSERID from the url and checks if it exists in the recover_db and if it does it lets them recover the account. There's some other stuff for security and whatnot but I do not store the user id in the recover_db , just the MD5 value of it. I use the following to do that:

md5(90*13/12*56+$id)

Now I need to check the users database and get the REAL account id using the md5 value I have saved. I was using the following query to do this:

$query = "SELECT uid FROM users where md5(90*13/12*56+uid)='".$md5accID."'";

Unfortunately this is returning no results. Is there any way to get the real user id from the users database using the md5 version of it from the recover_db ? I want to avoid storing the user id in the recover_db if I can.

Answer 1

Save the original user ID in a field origuid together with the hash ( hasheduid ) in the recovery database. Then do

$query = "SELECT origuid FROM users where hasheduid='".$md5accID."'";

to retrieve the original user ID.