How to get data from MySQL with PHP

Question

Hello all I am tryin to build IOS app and I need to get data my MySQL database. I do not know php. I found a tutorial https://codewithchris.com/iphone-app-connect-to-mysql-database/ In section 3 where we create PHP service I copy it and edit for mine information. PHP code is like that

<?php

//create connection
$con=mysqli_connect("localhost","myuserid","mypassword","i4142489_wp1");

// Check connection
if (mysqli_connect_errno())
{
    echo "Failed to connect to MySQL: " . mysqli_connect_error();
}

// This SQL statement selects ALL from the table 'Locations'
$sql = "SELECT * FROM treelibrary";

// Check if there are results
if ($result = mysqli_query($con, $sql))
{
    // If so, then create a results array and a temporary one
    // to hold the data
    $resultArray = array();
    $tempArray = array();

// Loop through each row in the result set
while($row = $result->fetch_object())
{
    // Add each row into our results array
    $tempArray = $row;
    array_push($resultArray, $tempArray);
}

// Finally, encode the array to JSON and output the results
echo json_encode($resultArray);
}

// Close connections
mysqli_close($con);

?>

I load it the my server and nothings pops up just the blank page... Is there any reason or where is my mistake. Thanks for helps. Have a nice day.

It looks like you only output something if executing the query was successful. If the query failed for some reason, you never reach an `echo` statement. Can you add an `else` condition in which you `echo mysqli_error($con);` (just for testing and debugging purposes)? — rickdenhaan, Sep 30 '18 at 13:03
@rickdenhaan I wrote it but nothing happen just a blank page again — Mertalp Tasdelen, Sep 30 '18 at 13:07
@MertalpTaşdelen I tested your code with my data, it was right. Check mysqli that is enable or not — Fatemeh Gharri, Sep 30 '18 at 13:12
If you don't get an error from your query, maybe something else is going wrong. If you [enable error reporting](https://stackoverflow.com/questions/1053424/how-do-i-get-php-errors-to-display), do you see any errors? — rickdenhaan, Sep 30 '18 at 13:13
@rickdenhaan I don't have php.ini file and don't know how to create one. I will try. — Mertalp Tasdelen, Sep 30 '18 at 13:18
@MertalpTaşdelen In a php file type `phpinfo();` and load the page to see what is enable or not enable in your server — Fatemeh Gharri, Sep 30 '18 at 13:22
@MertalpTaşdelen if mysqli be enable in your server you will see a table with the title of mysqli — Fatemeh Gharri, Sep 30 '18 at 13:32
@MertalpTaşdelen At the beginning of the code put `ini_set('display_errors', 1); ini_set('display_startup_errors', 1); error_reporting(E_ALL);` to load all warnings and errors on the page. then load your code again. — Fatemeh Gharri, Sep 30 '18 at 13:48
Let us [continue this discussion in chat](https://chat.stackoverflow.com/rooms/181017/discussion-between-mertalp-tasdelen-and-highlan). — Mertalp Tasdelen, Sep 30 '18 at 13:50

Mxlvin · Accepted Answer · 2018-09-30T13:45:22.577

I didn't read you're whole code, but I'm pretty sure you're trying to put the results into a JSON format and echo them.

Here's an easy way to do so;

<?php

//
// EDIT: dont use this code, scroll a little bit lower to see the edit I made.
//

//create connection
$con=mysqli_connect("localhost","myuserid","mypassword","i4142489_wp1");

// Check connection
if (mysqli_connect_errno())
{
    echo "Failed to connect to MySQL: " . mysqli_connect_error();
}

// This SQL statement selects ALL from the table 'Locations'
$sql = "SELECT * FROM treelibrary";

// Executes the SQL statement and puts results into $res
$res = $con->query($sql);

// Checks if there's any rows
if($res->num_rows > 0) {

    // Puts all results in $row
    $row = $res->fetch_assoc();

    // echo & encode datas
    echo json_encode($row);
} else {
    echo "no data found";
}

// Close connections
mysqli_close($con);

Edit: The code above does work but only echoes the first row. Here's one that actually echoes all of the rows in JSON format (tested).

<?php

//create connection
$con=mysqli_connect("localhost","myuserid","mypassword","i4142489_wp1");

// Check connection
if (mysqli_connect_errno())
{
    echo "Failed to connect to MySQL: " . mysqli_connect_error();
}

// This SQL statement selects ALL from the table 'Locations'
$sql = "SELECT * FROM treelibrary";

// Executes the SQL statement and puts results into $res
$res = $con->query($sql);

// Checks if there's any rows
if($res->num_rows > 0) {

    // defines $data
    $data = array();

    // grabs all data and adds them to the $data array
    while ($row =  $res->fetch_assoc()) {
        array_push($data, $row);
    }

    // echo & encode datas
    echo json_encode($data);
} else {
    echo "no data found";
}

// Close connections
mysqli_close($con);

I tried your code now but the same result maybe my `$con=mysqli_connect("localhost","myuserid","mypassword","i4142489_wp1");` line is wrong — Mertalp Tasdelen, Sep 30 '18 at 13:15
`Puts all results in $row` is incorrect, that only puts the first row in. — user3783243, Sep 30 '18 at 13:16
@user3783243after using the edited version of code resul is the blank page — Mertalp Tasdelen, Sep 30 '18 at 14:56
Then it's probably an error on your side, either you have no content in your database, of your database information is incorrect or you have some other code that's stopping it... Because I've tried it again, and it's still working... Something should always be printed on your screen because there's an IF & ELSE statement, and both has `echo()`. If you have discord, you can leave your discord tag and I'll dm you for further help. — Mxlvin, Sep 30 '18 at 15:12

How to get data from MySQL with PHP

1 Answers1