Fatal error: Uncaught mysqli_sql_exception: Unknown database 'test

Here is the code

<?php
$servername = "localhost";
$usrname   = "root";
$pwd = "";
$db = "test_db";
// connect to the database
$conn= mysqli_connect($servername, $usrname, $pwd,$db);
if (!$conn){
    die('connection failed' . mysqli_connect_error());
}
// Create database
$sql = "CREATE DATABASE IF NOT EXISTS test_db";
    if (mysqli_query($conn, $sql)) {
    echo "Database created successfully<br>";
} else {
  echo "Error creating database: " . mysqli_error($conn);
}
?>

I am not sure what is going on as I am sure i made no errors while typing. As it keeps showing me that there is an unknown database despite the fact i made a CREATE DATABASE statement. I do not know if there is something else i need to do but by all measures the code should work. It is supposed to echo the "Database created successfully" or the error message.

CodePudding user response：

`<?php
$servername = "localhost";
$usrname   = "root";
$pwd = "";
//$db = "test_db";
// connect to the database
$conn= mysqli_connect($servername, $usrname, $pwd);
if (!$conn){
    die('connection failed' . mysqli_connect_error());
}
// Create database
$sql = "CREATE DATABASE IF NOT EXISTS test_db";
    if (mysqli_query($conn, $sql)) {
    echo "Database created successfully<br>";
} else {
  echo "Error creating database: " . mysqli_error($conn);
}
?>`

Your code is fine, You just have to remove $db from mysqli_connect(). Because you are requesting to connect "test_db" to this database which already not exists.

CodePudding user response：

<?php
// Connect to MySQL
$link = mysql_connect('localhost', 'mysql_user', 'mysql_password');
if (!$link) {
    die('Could not connect: ' . mysql_error());
}

// Make my_db the current database
$db_selected = mysql_select_db('my_db', $link);

if (!$db_selected) {
  // If we couldn't, then it either doesn't exist, or we can't see it.
  $sql = 'CREATE DATABASE my_db';

  if (mysql_query($sql, $link)) {
      echo "Database my_db created successfully\n";
  } else {
      echo 'Error creating database: ' . mysql_error() . "\n";
  }
}

mysql_close($link);
?>

Reference How do I create a database if it doesn't exist, using PHP?

CodePudding user response：

$conn= mysqli_connect($servername, $usrname, $pwd,$db);

You are trying to connect to a database that did not initially exist, so you get a fatal error.

Try creating new database using try catch blocks

try{
$conn= mysqli_connect($servername, $usrname, $pwd,$db);
}cath(Exception $e){
//your code
}