PHP and mysql connection not working - php

Question

I have written following code to connect mysql in php but I am not getting output.
<?php
$servername = "localhost";
$username = "root";
$password = "pravin";
$mysql_conn = new mysqli($servername, $username, $password);
if ($mysql_conn->connect_error) {
die("Connection failed: ". $mysql_conn->connect_error);
}
echo "Connected successfully";
$name = $_POST["microorganism"];
echo $name;
$db_selected = mysql_select_db('yieldofvanillin', $mysql_conn);
if (!$db_selected){
die ('Can\'t use : ' . mysql_error());
}
$query = "SELECT * FROM vanillin WHERE Microorganism = '$name' ";
$result = $mysql_query($query);
while ($line = myql_fetch_array($result, MYSQL_ASSOC)) {
echo $line["Substrate"];
echo $line["products"];
echo $line["Microorganism"];
echo $line["yield"];
echo $line["Reference"];
}
mysql_close($mysql_conn);
?>
The database name is "yieldofvanillin" and it has five column. I an getting output Connected successfully. After that no output. Please let me know the bug in code.

Answer 1

i have remove errors. which i mention in comments. Code Reference PHP Manual. you should read this manual (strongly recommended)
<?php
$mysqli = new mysqli("localhost", "root", "pravin", "yieldofvanillin");
/* check connection */
if ($mysqli->connect_errno) {
printf("Connect failed: %s\n", $mysqli->connect_error);
exit();
}
$query = "SELECT * FROM vanillin WHERE Microorganism = '$name' ";
if ($result = $mysqli->query($query)) {
/* fetch associative array */
while ($row = $result->fetch_assoc()) {
echo $row["Substrate"];
echo $row["products"];
echo $row["Microorganism"];
echo $row["yield"];
echo $row["Reference"];
}
/* free result set */
$result->free();
}

Answer 2

you're mixing mysqli and mysql libraries.
the code should be:
<?php
$servername = "localhost";
$username = "root";
$password = "pravin";
$mysql_conn = new mysqli($servername, $username, $password);
if (mysqli_connect_errno()) {
die("Connection failed: ". mysqli_connect_error());
}
echo "Connected successfully";
$name = $_POST["microorganism"];
echo $name;
$db_selected = mysqli_select_db($mysql_conn,'yieldofvanillin');
if (!$db_selected){
die ('Can\'t use : ' . mysqli_error($mysql_conn));
}
$query = "SELECT * FROM vanillin WHERE Microorganism = '$name' ";
$result = mysqli_query( $mysql_conn,$query);
while ($line = mysqli_fetch_assoc($result)) {
echo $line["Substrate"];
echo $line["products"];
echo $line["Microorganism"];
echo $line["yield"];
echo $line["Reference"];
}
mysqli_close($mysql_conn);
?>

Answer 3

Remove error in your code.Read carefully php manual.
<?php
$servername = "localhost";
$username = "root";
$password = "pravin";
$db = "yieldofvanillin";
// Create connection
$mysqli = new mysqli($servername, $username, $password, $db);
/* connection string*/
if ($mysqli->connect_errno) {
die("Connection failed: " . $mysqli->connect_error);
exit();
}
$query = "SELECT * FROM vanillin WHERE Microorganism = '$name' ";
if ($result = $mysqli->query($query)) {
while ($row = $result->fetch_assoc()) {
echo $row["Substrate"];
}
$result->free();
}
$mysqli->close();
?>
Your output not showing because mysql_fetch_array is not correct.Because you are mixing mysql_ and mysqli_ functions and you called myql_fetch_array that doesn't exist in mysqli. MySQL and MySQLi are two different PHP extensions and they cannot be mixed. Because the former is deprecated in mysqli