PHP受影响的行返回0，但查询执行

Question

I have a function where I do an update to a table, after I call it I check the table and the row has changed but the functions returns "Error at update" instead of "Doctor occupied". Here is my function.

function funcion(){
    $con = new Conexion();
   $con->conecta();

   $sql = “SELECT * FROM llamada WHERE id_llamada = $id_llamada AND id_medico = $id_medico”;
   $res = $con->consulta($sql);
   if ($res->num_rows > 0) {
     $sql = “UPDATE medico SET disponible = 1 WHERE id_medico = $id_medico”;
     $con->consulta($sql);
     // var_dump($con->mysqli->affected_rows);
     if ($con->mysqli->affected_rows() > 0) {
       return [true,‘Doctor occupied’];
     }else{
       return [false,‘Error at update’,$con->mysqli];
     }
   }else{
     return [false,‘Data doesn't match’];
   }
}

The function conecta() does the connection with mysql.

Here is the class.

class Conexion {
    public $mysqli;

    public function conecta(){
        $this->mysqli = new mysqli(‘SERVER’, ‘USER’, ‘PASSWORD’, ‘DATABASE’);
        if ($this->mysqli->connect_errno) {
           echo “Fallo al conectar a MySQL: (” . $this->mysqli->connect_errno . “) ” . $this->mysqli->connect_error;
        }
        //echo $this->mysqli->host_info . “<br>“;
    }

    public function desconecta(){
        $this->mysqli->close();
    }

    public function consulta($sql) {
        $resultado = $this->mysqli->query($sql);
        if (!$resultado) {
            echo “Error en la consulta <br>“;
        }
        if (is_null($resultado)){
            echo “sin resultados”;
        }else{
            return $resultado;
        }
    }
}

Answer 1

Assuming that $con->mysqli is the connection handle, affected_rows is a property and not a method. So your line...

if ($con->mysqli->affected_rows() > 0) {

should be

if ($con->mysqli->affected_rows > 0) {

Which is how you use it in...

// var_dump($con->mysqli->affected_rows);

Answer 2

mySqli offers two interfaces, one object oriented and the other procedural. In the object-oriented manner, affected_rows is indeed a property of the mySqli object. However, if you are more comfortable using procedural coding, then one could use the function mysqli_affected_rows () which needs a $link parameter (see more info here ).

An example of the procedural option:

<?php
$link = mysqli_connect("localhost", "my_user", "my_password", "world");
// code for a SELECT, INSERT, UPDATE, REPLACE, or DELETE query
printf("Affected rows: %d\n", mysqli_affected_rows($link) );

Note: you may also find a good tutorial on the procedural style here .