Help me debug my SQL INSERT, please? - php

Question

I am pulling back some data from the twitter query API, and parsing it through PHP like so:
$i =0;
foreach ($tweetArray->results as $tweet) {
$timeStamp = strtotime($tweet->created_at);
$tweetDateTime = date('m-d-Y H:m:s', $timeStamp);
if($i > 0){
$SQL .= ',';
}
$SQL .= "(". $tweet->id .",'" . $tweet->from_user ."','". addslashes($tweet->profile_image_url) . "','". addslashes($tweet->text). "','" . $tweetDateTime ."')";
$i++;
}
$SQL .= " ON DUPLICATE KEY UPDATE 1=1";
This leaves me with a SQL statement looking like this:
INSERT
INTO
tblTwitterSubmit (tweetId, twitterAuthor, authorAvatar, tweetText, tweetDateTime)
VALUES
(111,'name','http://url.com','a string of text','03-04-2011 13:03:09'),
(222,'anothername','http://url.com','another tweet','03-04-2011 12:03:51')
ON DUPLICATE KEY UPDATE 1=1;
I am unfortunately getting the following error: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '1=1' at line 1.
Edit:
The 1=1 is supposed to not do anything. The tweets don't change, and so if I pull the same one back twice for any reason, nothing will happen, but it also won't throw a duplicate key error.
Re-edit:
The problem appears to have something to do with the key field I was using, which was the id of tweet as assigned by twitter.
I re-factored the code anyway, since it seemed pretty evident that what I had read in articles as a "really-good-idea" wasn't. I now included a PDO submit inside the for loop so I just make a bunch of submissions instead of one long sql string.
Hopefully this is better practice.
Leaving this open for a couple minutes hoping for some feedback if this is the way to do it or not.

Answer 1

The ON DUPLICATE KEY UPDATE requires a column name, something like this, assuming tweetId is the key column that's getting duplicates.
ON DUPLICATE KEY UPDATE tweetId=tweetId+1
Your 1=1 doesn't actually do anything.

Answer 2

Are you sure you're using the right syntax for on duplicate key update ?
Judging from it's manual's page, it seems you have to specify a column name, and not 1=1.
From what I understand, if you want to indicate "use the value from the values() clause when there's a duplicate", you should use something like this :
on duplicate key update your_col=values(your_col)
Quoting the relevant part :
You can use the VALUES(col_name)
function in the UPDATE clause to
refer to column values from the
INSERT portion of the INSERT ... ON
DUPLICATE KEY UPDATE statement.
In other words,
VALUES(col_name) in the ON
DUPLICATE KEY UPDATE clause refers to
the value of col_name that would be
inserted, had no duplicate-key
conflict occurred. This
function is especially useful in
multiple-row inserts.
Then, as a sidenote, you must escape your strings using the function that matches your API -- probably mysql_real_escape_string -- and not the generic addslashes, which doesn't know about the specificities of your database engine.

Answer 3

The problem appears to have something to do with the key field I was using, which was the id of tweet as assigned by twitter.
I re-factored the code anyway, since it seemed pretty evident that what I had read in articles as a "really-good-idea" wasn't. I now included a PDO submit inside the for loop so I just