Question

I have built a php script that saves results from a hash tag search and when I save the tweet ID it just tries saving a duplicate.
I have set a UNIQUE constraint on the table and it obviously doesn’t save anything but the first tweet and it throws the error below. Which isn’t surprising

ERROR: SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry '2147483647' for key 2

If I remove the constraint it saves all the tweets correctly but the tweet ID is duplicated

I have tried displaying the tweet in the output from the same variable I’m using to put in the table and it is all UNIQUE and correct so the variable is correct. So I can only assume some weirdness is going on all by itself

foreach($results as $result) {
$tweet_ID = $result->id_str;
$userID = $result->from_user_id_str;
$tweetText = $result->text;
$tweet_time = strtotime($result->created_at);
$createdAt = date('Y-m-d H:i:s ',$tweet_time);

echo '<div>'. $tweet_ID . 
     '<div class="tweet" >' . displayTweet($result->text),"\r\n" .
        '<div class="user">'. '<strong>Posted </strong>' . date('j/n/y H:i:s ',$tweet_time). '<strong> By </strong>' . 
        '<a rel="nofollow" href="http://twitter.com/' . $result->from_user. '">' . $result->from_user .
        '</div>' .
     '</div>';  

// Execute query 
$stmt = $conn->prepare("INSERT INTO ".$hashtag."(tweetID, userID, tweetText, createdAt) VALUES(:tweetID, :userID, :tweetText, :createdAt)");
$stmt->execute(array(':tweetID' => $tweet_ID, ':userID' => $userID, ':tweetText' => $tweetText, ':createdAt' => $createdAt));
}
} catch(PDOException $e) {
    echo 'ERROR: ' . $e->getMessage();
}

I can’t figure out for the life of me why it is saving some random numbers

The number that it is adding is 2147483647. Doesn’t mean anything to me.
Any help on what is going on would be appreciated

Answer 1

This number 2147483647 clearly indicates that you are not using 64-bit integers to store tweet id. Tweet ids are 64-bit integers. You should use BIGINT data type for tweetID column.

`tweetID` BIGINT UNSIGNED

The special value you are getting 2147483647 is because all the upper bits are truncated when a 64-bit tweet id is cast to 32-bit signed int. If you could have use unsigned int The number would have been higher. But not more than 2147483647*2. Tweet ids are much higher than that. You have to use 64-bit unsigned int

Also I see you are using a dynamic table name for your insert query. Dont do that! One single table can hold a lot of rows before you experience performance problem.