Warning: mysqli_query() expects parameter 2 to be string, object given in

Question

Good morning!

I\'m new in PHP. i\'m trying to make work this scrpt but is showing me this problem. It\'s a forma that modifies some records in a mysql database. The

Answer 1

Read the mysqli reference and learn from the error given

your error is that mysqli_query expects seconnd parameter to be a string but you are not giving a string variable as the argument.

mysqli_query($con,$query) $query is string and $con is object.

Your solution is to make $muestra to be a string.

$muestra="SELECT * FROM clientes C INNER JOIN producto P ON C.serial  = P.serial WHERE P.serial = $_GET[serial]";

Answer 2

Change

$muestra=$con->query("SELECT * FROM clientes C 
INNER JOIN producto P ON C.serial  = P.serial WHERE P.serial = $_GET[serial]");

To

// Updated to clean the input

$serial = mysqli_real_escape_string($con,$_GET[serial]) ;

$qry="SELECT * FROM clientes C 
INNER JOIN producto P ON C.serial  = P.serial WHERE P.serial = $serial";

Then

$muestra = mysqli_query($con,$qry);