Mysqli_Affected_rows总是返回0

Question

您好我正在尝试使用mysqli_affected_rows函数，但它总是返回0可以有人帮忙。试图通过MSQLI OOP完成它。

<?php
$servername ="localhost";
$username ="root";
$password ="testdb";
$database ="mydb";

$conn = new mysqli($servername, $username, $password, $database);

if($conn->connect_error)
{
die ("The Database connection is not established : " .connect_error);
}
echo "connection established";

//editing record

$sql_update = "update mytbl SET fname='Nitin Sharma' where sr=2";
echo "The affected Rows :" .mysqli_affected_rows($conn);
$conn->close(); 
?>  

表值：

Answer 1

您错过了执行SQL查询。

$conn->query($sql_update);

Answer 2

您需要先mysqli_query

执行查询

$sql_update = "update mytbl SET fname='Nitin Sharma' where sr=2";
$conn->mysqli_query($sql_update);
echo "The affected Rows :" .$conn->affected_rows;