Question

I have this query which I run in phpMyAdmin

SELECT m.msgFrom, m.msgTo, m.msgID, m.subject, m.dateTime, a.username
FROM mailbox m
JOIN accounts a ON ( a.id = IF( m.msgTo =1, m.msgFrom, m.msgTo ) ) 
WHERE msgTo =1
OR msgFrom =1
AND parentID =0
AND IF( m.msgTo =1, m.fromDelete, m.toDelete ) !=1
ORDER BY DATETIME DESC 
LIMIT 250

And I get a rowset of 0.

When using it with PDO PHP and placeholders like so,

$q = $dbc -> prepare("
SELECT m.msgFrom, m.msgTo, m.msgID, m.subject, m.dateTime, a.username 
FROM mailbox m JOIN accounts a ON (a.id = IF(m.msgTo = ?, m.msgFrom, m.msgTo)) 
WHERE msgTo = ? OR msgFrom = ? AND parentID = 0 AND IF(m.msgTo = ?, m.fromDelete, m.toDelete) != 1 
ORDER BY dateTime DESC LIMIT 250");
$q -> execute(array($user['id'], $user['id'], $user['id'], $user['id']));

I get a rowset of 1 where $user[id'] == 1.

What is going on here, and how can I fix it?

Answer 1

AND have an stronger binding than OR in mysql

WHERE msgTo =1
OR msgFrom =1
AND parentID =0
AND IF( m.msgTo =1, m.fromDelete, m.toDelete ) !=1

means

WHERE msgTo =1
OR (msgFrom =1
AND parentID =0
AND IF( m.msgTo =1, m.fromDelete, m.toDelete ) !=1)

PDO maybe handles this in another way

try

WHERE (msgTo =1
OR msgFrom =1)
AND parentID =0
AND IF( m.msgTo =1, m.fromDelete, m.toDelete ) !=1

in phpmyadmin