SQL查询语法（变量保持为空）

Question

I'm trying to output a simple list with all the usernames registered on a single e-mail address in our database. The SQL queries necessary for it shouldn't be too hard, but apparently they are too hard for me - here's my issue:

$sql = "SELECT emailaddress FROM ".db_prefix("accounts")." where acctid = '$mailid'";
$mailadress = db_query($sql);

That one's working just fine - I'm declaring mailid in a earlier part of the code, and with that query I can output the e-mail adress (for debugging) of the currently logged in user without any problems. Fine so far.

$sql = "SELECT name FROM ".db_prefix("accounts")." where emailadress ='$mailadress'";
$charakterliste = db_query($sql);

Here's the issue: $charakterliste seems to stay empty, even though I'm pretty sure my syntax is correct. var_dump() and print_r() don't return anything that would point towards the array/variable containing something.

I've double checked and executed a similar query directly in the SQL database and found no problems there - all the fields I'm calling do exist, and the DB connection is fine too. I guess something is wrong in my syntax for the second SQL query? I'd want to list all the names saved in the $charakterliste afterwards with a foreach loop, but as of now there doesn't seem to be anything to list saved in there, although there should be.

Thanks in advance!

Answer 1

Are you sure the column 'emailadress' exist?

Maybe it's 'emailaddress' with two 'd'?

According to your first line of code it should be 'emailaddress'.

$sql = "SELECT name FROM ".db_prefix("accounts")." where emailaddress ='$mailadress'";
$charakterliste = db_query($sql);