Arduino not sending numbers to SQL (via PHP) correctly - php

Question

So, basically I'm trying to get some values from an Arduino board to be saved to my SQL database stored on my PC.
I've looked at multiple resources online, and spent about 5-6 hours trying to crack this, but now i'm here asking for your help.
So, Heres what seems to be working.
Im able to send values to the database Directly by typing in :
[http://localhost/myapp/write_data.php?value1=2&value2=10]
to google chrome. This gives me the expected output from the PHP script and updates into the database. However, when I run it on the Arduino it goes through the code as if its working, but it isnt sending any data to the SQL Server.
Below is the Arduino Code.
#include <SPI.h>
#include <Ethernet.h>
int rand1 = 0;
int rand2 = 0;
//EthServer(80);
//IPAddress server(10,0,0,1);
char server[] =("10.0.0.1");
EthernetClient client;
byte mac[] = {
0x00, 0xAA, 0xBB, 0xCC, 0xDE, 0x0
};
byte ip[] = { 10, 0, 0, 2 };
void setup(void)
{
// start serial port
Serial.begin(9600);
Ethernet.begin(mac, ip);
}
void printIPAddress()
{
Serial.print("My IP address: ");
for (byte thisByte = 0; thisByte < 4; thisByte++) {
// print the value of each byte of the IP address:
Serial.print(Ethernet.localIP()[thisByte], DEC);
Serial.print(".");
}
Serial.println();
}
void loop() {
delay(1000);
rand1 = random(1, 3);
rand2 = random(25);
Serial.println(rand1);
Serial.println(rand2);
// Connect to the server (your computer or web page)
if (client.connect(("http://10.0.0.1"), 80)) {
client.print("GET /myapp/write_data.php?"); // This
client.print("value1="); // This
client.print(rand1); // And this is what we did in the testing section above. We are making a GET request just like we would from our browser but now with live data from the sensor
client.print(";");
client.print("value2=");
client.print(rand2);
client.println(" HTTP/1.1"); // Part of the GET request
client.println("Host: 10.0.0.1"); // IMPORTANT: If you are using XAMPP you will have to find out the IP address of your computer and put it here (it is explained in previous article). If you have a web page, enter its address (ie.Host: "www.yourwebpage.com")
client.println("Connection: close"); // Part of the GET request telling the server that we are over transmitting the message
client.println(); // Empty line
client.println(); // Empty line
client.stop(); // Closing connection to server
}
else {
// If Arduino can't connect to the server (your computer or web page)
Serial.println("--> connection failed\n");
printIPAddress();
}
delay(10000);
}
Then here I have the PHP Script
//connect
$link=new mysqli("localhost", "root", "", "myappdb");
//check connection
if ($link==false) {
die("Connection failed: " . mysqli_connect_error());
}
//insert values
$sql = "INSERT INTO resistence (phase, max_reading)
VALUES (". $_GET['value1'] .",". $_GET['value2'].")";
//// Check if values have been inserted, confirm with user that values are correct.
if(mysqli_query($link, $sql)){
echo "Records inserted successfully.";
echo "Values inserted are Phase " . $_GET['value1']. " and Max_Reading ". $_GET['value2']. ".";
}
else
{
echo "ERROR: Could not able to execute $sql. " . mysqli_error($link);
}
/////
//close connection
mysqli_close($link);
?>
Any help at all would be awesome.
Cheers
John

Answer 1

If you don't get reponse "connection failed" then it should be connected. Try
client.print("&");
instead
client.print(";");
If that still doesn't work, in the PHP file, use
error_log("text");
and check the server error.log to figure out if PHP script is even started, and check if $_GET variable is set at all.
EDIT: addition:
You shouldn't use client.connect in if statement.
client.connect returns an int (1,-1,-2,-3,-4) indicating connection status
SUCCESS 1
TIMED_OUT -1
INVALID_SERVER -2
TRUNCATED -3
INVALID_RESPONSE -4
So print out the return and then continue with debugging. Must be problem with the IP address you provided.