Object of class mysqli_result could not be converted to string

[yami]

$resulti = mysqli_query($connection , "INSERT INTO cart(idItem,idUser) VALUES('$idd','$iduser')");
				
					if(!$resulti){
						die('Query failed!' . mysqli_error($connection));
					  }

I am just trying to insert some data into a db table but this error keeps showing..any ideas how to fix it?

[ginerjm]

Are you sure about the line?  I don't see any attempt to convert a var unless it is the two Values in your query statement.  Try separating the query build from the query call and see what happens.

$q  =......

mysqli__query($connection, $q);

[yami]

I tried that too..I tried to separate them but it shows the same error!

I have the same query in another php file but it does not show any error so I cannot tell what is wrong..

[ginerjm]

Could we see the code you are now using as well as the exact error message?  And be sure to point us to the line number

[yami]

So I have an if-else statement full of queries and it is the else part where there is an error and here it is:

else{
				$nameuser = $_SESSION['username'];
				$iduser = $connection->query("SELECT idCustomer FROM customer WHERE username='$nameuser'");
				if(!$iduser){
					die('Query failed!' . mysqli_error($connection));
				  }

				if (isset($_POST['idd']) && $_POST['idd']!=""){
					$idd = $_POST['idd'];
				// echo $idd;
			
	
				// $query ="INSERT INTO cart(idItem,idUser) VALUES('$idd','$iduser')";
				$resulti = mysqli_query($connection , "INSERT INTO cart(idItem,idUser) VALUES('$idd','$iduser')");
				
					if(!$resulti){
						die('Query failed!' . mysqli_error($connection));
					  }
				

			}
		}

<input type='hidden' name='idd' id='idd' >

the exact error message: Catchable fatal error: Object of class mysqli_result could not be converted to string in C:\wamp64\www\index.php on line 134

it is the last query's line

is it enough?

[Barand]

Your problem is with $iduser

It is the result of the first query yet you are attemping to insert it as a value in the second query. You need to fetch the id from the resultset to use its value.

Edited March 25, 2022 by Barand

[yami]

ahh got it..it worked! Thank you @Barand