无法在php中使用prepare和bind_param

Question

I am having trouble using prepare and bind_param statements in php. My code is as follows:

<?php


$dbhost = 'localhost'; //default
$dbuser = 'root';
$dbpass = ‘somepassword’;
//Create a connection object
$conn = new mysqli($dbhost, $dbuser, $dbpass);
if($conn->connect_error )
{
  die('Could not connect: %s' . $conn->connect_error);
}
echo "Connected successfully<br>";

$conn->select_db("TUTORIAL");

$stmt=$conn->prepare("INSERT INTO tutorial_info (tutorial_title,tutorial_author) VALUES (?,?)");
$stmt->bind_param("sss",$tutorial_title,$tutorial_author);

//try and insert
$tutorial_title=“English Lit”;
$tutorial_author=“Bob Trotter”;
$stmt->execute();





//Close the database
$conn->close();




 ?>

When I execute the script I get the message "connected successfully" however if I check the table contents the new row has not been added. Any ideas what I might be doing wrong here?

I also see in the documentation that in bind_param we add an additional parameter ie $stmt->bind_param( "sss" ,$tutorial_title,$tutorial_author); In this case it is "sss". What is it used for? Can I get rid of it?

Any pointers would be really appreciated! thanks

Answer 1

The first parameter of bind_param describes the types of the parameters. RTM!

You can specify s for string and i for integer for example. The number of characters in the first parameters have to cover the number of the other parameters exactly.

Answer 2

Try this code

<?php


$dbhost = 'localhost'; //default
$dbuser = 'root';
$dbpass = ‘somepassword’;
//Create a connection object
$conn = new mysqli($dbhost, $dbuser, $dbpass);
if($conn->connect_error )
{
  die('Could not connect: %s' . $conn->connect_error);
}
echo "Connected successfully<br>";

$conn->select_db("TUTORIAL");

$stmt=$conn->prepare("INSERT INTO tutorial_info (tutorial_title,tutorial_author) VALUES (?,?)");
$stmt->bind_param("ss",$tutorial_title,$tutorial_author);

//try and insert
$tutorial_title=“English Lit”;
$tutorial_author=“Bob Trotter”;
$stmt->execute();





//Close the database
$conn->close();




 ?>

Answer 3

Remove extra s

$stmt=$conn->prepare("INSERT INTO tutorial_info (tutorial_title,tutorial_author) VALUES (?,?)");
$stmt->bind_param("ss",$tutorial_title,$tutorial_author);