Inserting data into database with pdo prepared statment - php

Question

Inserting data into database with pdo prepared statment, doesnt work for me:
I use this function:
public function get_number_of_matches(){
$stmt = $this->pdo->prepare("INSERT INTO `words`( `word_name`, `word_count`, `search_id`) VALUES (:word, :count,:searchID)");
$stmt->bindParam(':word', $word);
$stmt->bindParam(':count', $count);
$stmt->bindParam(':searchID', $search_id);
for($i=0;$i<count($this->words);$i++){
if(preg_match_all('/'.$this->words[$i].'/i', $this->text,$matches)){
$count=count($matches[0]);
$word=$this->words[$i];
$search_id=1;
$stmt->execute();
break;
}
}
return 0;
}
Basically, I try to loop over the values and put them into the database.. no error is given.. nothing goes into the database ..why?
This is how I connect to the database:
class DBConnection {
public static $connect;
public static function connect(){
if(!isset(self::$connect)){
try{
self::$connect=new PDO('mysql:host=localhost;dbname=tweeter', 'root', '');
}catch(Exception $ex){
echo $ex->getMessage();
}
}
return self::$connect;
}
}
UPDATE
Also..see here:
I do the same thing with a different query..but when I try to put object properties inside a variable I get an error:
$tweet= $tweet->tweet ;
$user=$tweet->tweeter_name;
$link= $tweet->link;
Those variables go into a query:
$pdo= DBConnection::connect();
$stmt = $pdo->prepare("INSERT INTO `tweets`( `tweet`, `tweeter_name`, `link`, `date`, `search_id`) VALUES (:tweet, :tweeter_name, :link, :date, :search_id)");
$stmt->bindParam(':tweet', $tweet);
$stmt->bindParam(':tweeter_name', $user);
$stmt->bindParam(':link', $link);
$stmt->bindParam(':date', $date);
$stmt->bindParam(':search_id', $search_id);
I get errors like this:
Notice: Trying to get property of non-object in C:\xampp\htdocs\Twitter\demo.php on line 36
Notice: Trying to get property of non-object in C:\xampp\htdocs\Twitter\demo.php on line 37
Notice: Trying to get property of non-object in C:\xampp\htdocs\Twitter\demo.php on line 38
I can print the properties..but when allocating them to those binded variables..the above errors crop up
I get also this:
Fatal error: Uncaught exception 'PDOException' with message 'SQLSTATE[23000]: Integrity constraint violation: 1048 Column 'tweeter_name' cannot be null' in C:\xampp\htdocs\Twitter\demo.php:40 Stack trace: #0 C:\xampp\htdocs\Twitter\demo.php(40): PDOStatement->execute() #1 {main} thrown in C:\xampp\htdocs\Twitter\demo.php on line 40
I checked instead like this:
$tweet= "111111"; // $tweet->tweet ;
$user= "22222222"; // $tweet->tweeter_name;
$link= "3333333"; // $tweet->link;
$date= "444444";
and it worked..for some reason it hates those object properties ?!?
This should go as input:
RT #OrganicLiveFood: Scientists Warn #EPA Over #Monsanto's #GMO Crop Failures & Dangers #prop37 #labelGMO #yeson37 http://t.co/2XhuVxO8
Doumastic
TweetCaster for iOS
Mon, 19 Nov 2012 20:40:55 +0000
RT #OrganicLiveFood: Scientists Warn #EPA Over #Monsanto's #GMO Crop Failures & Dangers #prop37 #labelGMO #yeson37 http://t.co/2XhuVxO8
But it doesnt...?!?

Answer 1

Add self::$connection->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); right after connecting.
It would make sure PDO will throw PDOExceptions on every error, making them very easy to see. The error would then outline exactly what's wrong.

Answer 2

Check the return value from $stmt->execute(), if there was a problem it will return false and you should check $stmt->errorInfo() for details.
Or else use the ERRMODE_EXCEPTION that #Madara Uchiha suggests, but if you're not already handling exceptions in your application, this can be hard to adapt to.
Re: your update.
You should check error status from both PDO::prepare() and PDOStatement::execute() every time you call them. The error about "Trying to get property of non-object" likely means that $stmt is actually the boolean value false instead of a valid PDOStatement object. Your call to $stmt->bindParam() fails because false is not an object, so it cannot have a bindParam() method.
In my opinion it's much easier to pass parameters by value instead of binding variables by reference. Here's an example of both error-checking and parameters by value:
$pdo = DBConnection::connect();
$sql = "INSERT INTO `tweets`( `tweet`, `tweeter_name`, `link`, `date`, `search_id`)
VALUES (:tweet, :tweeter_name, :link, :date, :search_id)";
if (($stmt = $pdo->prepare($sql)) === false) {
die(print_r($pdo->errorInfo(), true));
}
$params = array(
':tweet' => $tweet,
':tweeter_name' => $user,
':link' => $link,
':date' => $date,
':search_id' => $search_id
);
if (($status = $stmt->execute($params) === false) {
die(print_r($stmt->errorInfo(), true));
}
The error "Column 'tweeter_name' cannot be null'" that you saw in the exception means that your tweeter_name column is declared NOT NULL, but your $user variable had no value when you bound it to the :tweeter_name parameter.