Android Question MySQL and PHP problem

[elproing]

Hello everyone,

I have an application on my Android with select and insert statement on MySQL database over .php script on my server. When I do a SELECT statement everything is working perfect. When I do an INSERT statement I get an error in B4A logs wich occurs occasionally.

ResponseError. Reason: Internal Server Error, Response: PHP Warning: mysqli_fetch_assoc() expects parameter 1 to be mysqli_result, boolean given in C:\inetpub\wwwroot\GetDataSQL_B4A.php on line 21
PHP Warning: mysqli_free_result() expects parameter 1 to be mysqli_result, boolean given in C:\inetpub\wwwroot\GetDataSQL_B4A.php on line 26

My php code in GetDataSQL_B4A.php is:

<?php

$databasehost = "localhost";
$databasename = "mydatabase";
$databaseusername ="myuser";
$databasepassword = "mypass";

$con = mysqli_connect($databasehost,$databaseusername,$databasepassword, $databasename) or die(mysqli_error($con));
mysqli_set_charset ($con , "utf8");
$query = file_get_contents("php://input");
$sth = mysqli_query($con, $query);

if (mysqli_errno($con)) {
    header("HTTP/1.1 500 Internal Server Error");
    echo $query.'\n';
    echo mysqli_error($con);
}
else
{
    $rows = array();
    while($r = mysqli_fetch_assoc($sth)) {
        $rows[] = $r;
    }
    $res = json_encode($rows);
    echo $res;
    mysqli_free_result($sth);
}

mysqli_close($con);
?>

Why Am I getting this error?

 

[sorex]

you need to skip the fetching as an insert doesn't return records.

use switch and parameters via post to select what you want to do.

 

[aeric]

$query = file_get_contents("php://input");

I think you should pass an SQL statement to $query

 

[DonManfred]

I think you should pass an SQL statement to $query

based on the file_get_contents("php://input") he is posting the query from B4A to the php-script. #2 from @sorex is more approbiate.

Away from that using this Methods opens all doors for any kind of SQL-Injection.
I would NOT, NEVER!, send the complete Query. Only parameters and i would always create the Query in my PHP-Script.

 

[aeric]

posting the query from B4A to the php-script

I don't think this is a proper way. I normally use file_get_contents to upload image or file.

I don't use mysqli nowadays. For me, PDO is better.

 

[DonManfred]

I don't think this is a proper way.

I fully agree.

Away from that using this Methods opens all doors for any kind of SQL-Injection.

 

[elproing]

I have used this code for inserting data into MySQL and it works perfect for me.

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDBPDO";

try {
    $conn = new PDO("mysql:host=$servername;dbname=$dbname", $username, $password);
    // set the PDO error mode to exception
    $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
    $sql = file_get_contents("php://input");

    // use exec() because no results are returned
    $conn->exec($sql);
    echo "INSERT OK";
    }
catch(PDOException $e)
    {
    echo $sql . "<br>" . $e->getMessage();
    }

$conn = null;
?>

Thank you everyone for help

Regards

 

[elproing]

Hello,

I have another problem. When I insert number with decimal (3.5) in my EditBox and I insert this number in MySQL, I get 3.49990054798 in my table. Why is that?


This is my part of the code in B4A:

InsertPressureStartFRM1=FunctionBlocks.FloatWrite(EditPressureStartFRM1)

and my function wich I call

Public Sub FloatWrite (EditFloatData As EditText) As Float
   
    Dim FloatData As Float
   
    If    EditFloatData.Text <> "" Then
       
        FloatData= Round2(EditFloatData.Text,1)
       
    Else
        If EditFloatData.Text = "" Then
            FloatData=0.0
        End If
    End If
   
    Return FloatData
   
End Sub

 

[Erel]

I have another problem

You should start a new thread for a new question.