Can't create table (errno: 150) on FOREIGN KEY - php

Question

I saw a lot of same question but I couldn't solve my case.
If I run this code:
<?php
include_once($_SERVER['DOCUMENT_ROOT'].'/config.php');
$servername = HOST;
$username = USERNAME;
$password = PASSWORD;
$dbname = DB;
// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
// sql to create table
$sql = "CREATE TABLE IF NOT EXISTS Articls (
id INT(10) UNSIGNED AUTO_INCREMENT PRIMARY KEY,
name VARCHAR(254) COLLATE utf8_persian_ci NOT NULL
) DEFAULT COLLATE utf8_persian_ci";
if ($conn->query($sql) === TRUE) {
echo "Table Articls created successfully";
} else {
echo "Error creating table: " . $conn->error;
}
/////////////////////////////////////////////////////////////////////////
$sql = "CREATE TABLE IF NOT EXISTS Tags (
id INT(10) UNSIGNED AUTO_INCREMENT PRIMARY KEY,
id_articls INT(10) UNSIGNED NOT NULL,
name VARCHAR(256) COLLATE utf8_persian_ci NOT NULL,
FOREIGN KEY(Tags.id_articls) REFERENCES Articls(Articls.id)
) DEFAULT COLLATE utf8_persian_ci";
if ($conn->query($sql) === TRUE) {
echo "Table Tags created successfully";
} else {
echo "Error creating table: " . $conn->error;
}
$conn->close();
?>
I get this error: ( If I remove FOREIGN KEY it works)
Table Articls created successfully Error creating table: Can't create
table 'admin_wepar.Tags' (errno: 150)
Edit
If a change into Articls.id and Tags.id_articls I got this error:
Table Articls created successfullyError creating table: You have an
error in your SQL syntax; check the manual that corresponds to your
MySQL server version for the right syntax to use near 'FOREIGN KEY
(Tags.id_articls) REFERENCES Articls(Articls.id) ) DEFAULT COLLA' at
line 5

Answer 1

You need to declare both Articls.id and Tags.id_articls signed or unsigned

Answer 2

Tags.id_articls is a signed integer while Articl.id is an unsigned integer. MySQL requires referencing field to be exactly the same type. Make Tags.id_articls unsigned to have it work.
Additionally, the table names in the column lists are not allowed in MySQL. It is always clear which table is meant: first the referencing table and then the referenced table. So change
FOREIGN KEY(Tags.id_articls) REFERENCES Articls(Articls.id)
into
FOREIGN KEY(id_articls) REFERENCES Articls(id)
and it will work.