mysqli_real_escape_string doesn't seem to be working - php

Question

I am a novice in PHP. I am trying to insert a variable's value into a MariaDB table and was trying to use mysqli_real_escape_string to escape '$value'.
I got the idea from here.
It inserted an empty string to the table(I did add a connection link to the database).
So, I copied and pasted the following code from PHP Manual, it still didn't work. The output I got was an error code alone: Error: 42000. What am I missing?
I am using a Virtualbox,
OS: CentOS7
<?php
$link = mysqli_connect("localhost", "my_user", "my_password", "world");
/* check connection */
if (mysqli_connect_errno()) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
mysqli_query($link, "CREATE TEMPORARY TABLE myCity LIKE City");
$city = "'s Hertogenbosch";
/* this query will fail, cause we didn't escape $city */
if (!mysqli_query($link, "INSERT into myCity (Name) VALUES ('$city')")) {
printf("Error: %s\n", mysqli_sqlstate($link));
}
$city = mysqli_real_escape_string($link, $city);
/* this query with escaped $city will work */
if (mysqli_query($link, "INSERT into myCity (Name) VALUES ('$city')")) {
printf("%d Row inserted.\n", mysqli_affected_rows($link));
}
mysqli_close($link);
?>
Update: Thank you for your prompt response! I tried #Pilan's code but I was not able to insert a row. I created a table in the database called 'City'. I checked whether there was a database connection in the code and it did return "Connected". Here is the updated code:
<?php
$link = mysqli_connect("localhost", "my_user", "my_password", "world");
/* check connection */
if (mysqli_connect_errno()) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
else {
echo "Connected";
$city = "'s Hertogenbosch";
// Connect to db, returns mysqli-connection
$mysqli = new mysqli("localhost", "my_user", "my_password", "world");
// Prepare, "?" for placeholders, returns mysqli-statement
$stmt = $mysqli->prepare("INSERT INTO City (Name) VALUES (?)");
// Bin param to statement, with type "s" for string
$stmt->bind_param("s", $city);
//Execute
/* this query with escaped $city will work */
if ($stmt->execute()) {
printf("%d Row inserted.\n", mysqli_affected_rows($link));
}
}
mysqli_close($link);
?>
Update: Thanks guys, The code worked, It did insert into the table but 'Row inserted' didn't show up: turns out, I forgot to take out the semicolon from 'execute()' inside if conditional statement.

Answer 1

Here you got an example of a prepared statement:
$city = "'s Hertogenbosch";
// Connect to db, returns mysqli-connection
$mysqli = new mysqli("localhost", "my_user", "my_password", "world");
// Prepare, "?" for placeholders, returns mysqli-statement
$stmt = $mysqli->prepare("INSERT INTO myCity (Name) VALUES (?)");
// Bin param to statement, with type "s" for string
$stmt->bind_param("s", $city);
// Well execute :D
$stmt->execute();
For details have a look here: prepare, bind