PHP Try and Catch for SQL Insert

Question

I have a page on my website (high traffic) that does an insert on every page load.

I am curious of the fastest and safest way to (catch an error) and continue if the

Answer 1

Elaborating on yasaluyari's answer I would stick with something like this:

We can just modify our mysql_query as follows:

function mysql_catchquery($query,$emsg='Error submitting the query'){
    if ($result=mysql_query($query)) return $result;
    else throw new Exception($emsg);
}

Now we can simply use it like this, some good example:

try {
    mysql_catchquery('CREATE TEMPORARY TABLE a (ID int(6))');
    mysql_catchquery('insert into a values(666),(418),(93)');
    mysql_catchquery('insert into b(ID, name) select a.ID, c.name from a join c on a.ID=c.ID');
    $result=mysql_catchquery('select * from d where ID=7777777');
    while ($tmp=mysql_fetch_assoc($result)) { ... }
} catch (Exception $e) {
    echo $e->getMessage();
}

Note how beautiful it is. Whenever any of the qq fails we gtfo with our errors. And you can also note that we don't need now to store the state of the writing queries into a $result variable for verification, because our function now handles it by itself. And the same way it handles the selects, it just assigns the result to a variable as does the normal function, yet handles the errors within itself.

Also note, we don't need to show the actual errors since they bear huge security risk, especially so with this outdated extension. That is why our default will be just fine most of the time. Yet, if we do want to notify the user for some particular query error, we can always pass the second parameter to display our custom error message.

Answer 2

mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);

I am not sure if there is a mysql version of this but adding this line of code allows throwing mysqli_sql_exception.
I know, passed a lot of time and the question is already checked answered but I got a different answer and it may be helpful.

Answer 3

$new_user = new User($user);
$mapper = $this->spot->mapper("App\User");

try{
    $id = $mapper->save($new_user);     
}catch(Exception $exception){

    $data["error"] = true;
    $data["message"] = "Error while insertion. Erron in the query";
    $data["data"] = $exception->getMessage();

    return $response->withStatus(409)
    ->withHeader("Content-Type", "application/json")
    ->write(json_encode($data, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT));        
}

if error occurs, you will get something like this->

{
    "error": true,
    "message": "Error while insertion. Erron in the query",
    "data": "An exception occurred while executing 'INSERT INTO \"user\" (...) VALUES (...)' with params [...]:\n\nSQLSTATE[22P02]: Invalid text representation: 7 ERROR:  invalid input syntax for integer: \"default\"" }

with status code:409.

Answer 4

This can do the trick,

function createLog($data){ 
    $file = "Your path/incompletejobs.txt";
    $fh = fopen($file, 'a') or die("can't open file");
    fwrite($fh,$data);
    fclose($fh);
}
$qry="INSERT INTO redirects SET ua_string = '$ua_string'"   
$result=mysql_query($qry);
if(!$result){
    createLog(mysql_error());
}

Answer 5

Checking the documentation shows that its returns false on an error. So use the return status rather than or die(). It will return false if it fails, which you can log (or whatever you want to do) and then continue.

$rv = mysql_query("INSERT INTO redirects SET ua_string = '$ua_string'");
if ( $rv === false ){
     //handle the error here
}
//page continues loading

Answer 6

Use any method described in the previous post to somehow catch the mysql error.
Most common is:

$res = mysql_query('bla');
if ($res===false) {
  //error
  die();
}
//normal page

This would also work:

function error() {
  //error
  die()
}
$res = mysql_query('bla') or error();
//normal page

try { ... } catch {Exception $e) { .... } will not work!

Note: Not directly related to you question but I think it would much more better if you display something usefull to the user. I would never revisit a website that just displays a blank screen or any mysterious error message.