Warning: mysqli_query() expects at least 2 parameters

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JanMolendijk
Posts: 282
Location: Holland Rotterdam

Warning: mysqli_query() expects at least 2 parameters

I did turn a php script to mysqli but getting two errors:

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Warning: mysqli_select_db() expects exactly 2 parameters, 1 given in /home/u790012824/public_html/Message/comments/db.php on line 26
Code:

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$db_hostname = "mysql.hostinger.nl";  //usually "localhost be default"
$db_username = "u790012824_gebru";  //your user name
$db_pass = "123456";  //the password for your user
$db_name = "u790012824_datab";  //the name of the database

/*MYSQL DATABASE CONNECTION/ TRACKING FUNCTIONS
--------------------------------------*/
// connect to database
$dbh = mysqli_connect ($db_hostname, $db_username, $db_pass) or die ('I cannot connect to the database because: ' . mysql_error());
mysqli_select_db ($db_name);
?>
line 26 is

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mysqli_select_db ($db_name);
my second error is the same

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Warning: mysqli_query() expects at least 2 parameters, 1 given in /home/u790012824/public_html/Message/comments/inc_rate.php on line 178
Code:

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function getComments($tutid){
//fetch all comments from database where the tutorial number is the one you are asking for
	$results = mysqli_query("SELECT * FROM comments WHERE qazi_id='$tutid' ORDER BY id DESC") or die(mysql_error());
//find the number of comments
	$commentNum = mysqli_num_rows($results);
line 178 is

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	$results = mysqli_query("SELECT * FROM comments WHERE qazi_id='$tutid' ORDER BY id DESC") or die(mysql_error());

Admin Posts: 805
Hy,
Replace the "mysqli_" prefix from the function name with the object that store the connection.
For example:

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// connect to database
$dbh = mysqli_connect($db_hostname, $db_username, $db_pass) or die ('I cannot connect to the database because: '. mysqli_connect_error());
$dbh->select_db($db_name);
Or, add the object with mysqli as first parameter to the "mysqli_...()" function.

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// connect to database
$dbh = mysqli_connect($db_hostname, $db_username, $db_pass) or die ('I cannot connect to the database because: '. mysqli_connect_error());
mysqli_select_db($dbh, $db_name);
- The same for mysqli_query() and other "mysqli_.." functions.

If the "mysqli_" is into a function, you must add in that function scope (with the GLOBAL keyword) the object with mysqli connection.

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function getComments($tutid){
  GLOBAL $dbh;  //to can use $dbh in this function
//fetch all comments from database where the tutorial number is the one you are asking for
   $results = $dbh->query("SELECT * FROM comments WHERE qazi_id='$tutid' ORDER BY id DESC");
//find the number of comments
  $commentNum = $results->num_rows;
  //...
}