Error handling and fetching MySQL data using PHP

Question

I'm running hosting through Godaddy and update the code direct on the server. Instead of running it local and then uploading it to the server. The only problem is that I don't get any error messages that I usually would get when I run it locally using WAMP.

Right now I'm trying to fetch data using MySQL, but I only get a blank page.

require_once('../db.php');

$countyArr = mysql_query(SELECT `County` FROM `Infectious_Disease_Cases_by_County`);

while($rows = mysql_fetch_array($countyArr))
{

   $rows = $rows['County'];

   echo $rows;
}


?>

db.php

<?php
    $username = "user";
    $password = "pass";
    $hostname = "localhost"; 
    $dbname = "db_test";


    try {
    $dbh = new PDO("mysql:host=$hostname;dbname=$dbname",$username,$password);

    $dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); // <== add this line
    echo 'Connected to Database<br/>';
    }
    catch(PDOException $e)
    {
    echo $e->getMessage();
    }
?>

Questions:

How do I activate error handling like the one I get with WAMP?
Where do I go wrong in this specific code?

You can't open the connection using PDO, then perform the query using mysql. — Barmar, Jan 16 '16 at 22:28

Shadow · Answer 1 · 2016-01-16T22:44:47.520

2

Php error reporting can be turned on using error_reporting() function. You also need to handle mysql errors. Handling them depends on your chosen module you use to connect to it.
There are 2 problems with your code that I can see. The sql command needs to be passed as string, so enclose it by " or '. Moreover, you connect to mysql via pdo, but you try to execute your sql command with mysql module. Use pdo to execute the sql command.

edited Jan 16 '16 at 22:44

answered Jan 16 '16 at 22:27

Shadow

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It's pretty clear; OP is mixing MySQL APIs here. – Funk Forty Niner Jan 16 '16 at 22:34
I know, that's what I wrote. Plus the issue with the command itself. – Shadow Jan 16 '16 at 22:35
Okay, that error_reporting() function seems to work! How would I call a query using PDO? – Adam Jan 16 '16 at 22:39
Added a link to my answer – Shadow Jan 16 '16 at 22:45

score 0 · Answer 2 · edited May 23 '17 at 12:04

0

You need put string inside quotes:

$countyArr = mysql_query("SELECT `County` FROM `Infectious_Disease_Cases_by_County`");

To display error in php:

Check this other question

edited May 23 '17 at 12:04

Community

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answered Jan 16 '16 at 22:20

Vinícius Fagundes

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what string? OP is using ticks in their query, just not the right API. – Funk Forty Niner Jan 16 '16 at 22:34
ah ok I see now what you mean. Well either way, that whole line needs to be scrapped. – Funk Forty Niner Jan 16 '16 at 22:37
@Fred-ii- the sql command is not a string in the OP. Even Barmar seem to have missed that. – Shadow Jan 16 '16 at 22:37
@Shadow Nonetheless, that line (edit: that whole query) needs to be changed to accomodate the PDO connection and is worthless really. I see no reason trying to fix something that won't work with the initial connection. Barmar's close is legit. – Funk Forty Niner Jan 16 '16 at 22:39
I see. The really problem was mixing APIs. – Vinícius Fagundes Jan 16 '16 at 22:39
So, should I delete my answer? – Vinícius Fagundes Jan 16 '16 at 22:41
@Fred-ii- I know, I pointed both things out in my answer. However, if the OP switches over to pdo to execute the sql query, but forgets to change the sql command to string, the code still will not work. – Shadow Jan 16 '16 at 22:41
@ViníciusFagundes that's up to you. If you feel that you can fix their query, go for it. – Funk Forty Niner Jan 16 '16 at 22:41
@Shadow the OP has a choice. PDO or mysql_, and not `&&`. – Funk Forty Niner Jan 16 '16 at 22:42
mysql_ is already deprecated, may use mysqli_ instead. – Vinícius Fagundes Jan 16 '16 at 22:47

Error handling and fetching MySQL data using PHP

2 Answers2