Dependent category subcategory dropdown in PHP, MySQL & Ajax

bro this is very helpful video for me....

Hello sir, this is nice tutorial. I need your help sir can you please make a tutorial on dynamic dropdown list crud operation project using php mysql and ajax.

I LIKE HOW YOU TEACH

Super! Thank You!

Hi, I have goe through the video and am having a problem with the sub category query. When I echo the sub cat query it gives me

SELECT * FROM categories WHERE parent_id =

the query in get_subcat.php is

$sql = "SELECT * FROM categories WHERE parent_id = $category_id";
$result = mysqli_query($conn, $sql);

The category dropdown is populated but the sub category isn't populating.

I am getting 1 notice and 1 warning

Notice: Undefined index: category_id in C:\xampp\htdocs\dependantdropdown2021\dependantdropdown2\get_subcat.php on line 4
Select Sub Category

Warning: mysqli_fetch_array() expects parameter 1 to be mysqli_result, boolean given in C:\xampp\htdocs\dependantdropdown2021\dependantdropdown2\get_subcat.php on line 14
SELECT * FROM categories WHERE parent_id =

could you advise please?

I also copied and pasted your code into my files but still have the same issues.

Notice: Undefined index: category_id in C:\xampp\htdocs\dependantdropdown2021\dependantdropdown2\get_subcat.php on line 3

Select Sub Category

Warning: mysqli_fetch_array() expects parameter 1 to be mysqli_result, boolean given in C:\xampp\htdocs\dependantdropdown2021\dependantdropdown2\get_subcat.php on line 8

Thanks

hlo r u thare

Thanks for video

🙏🙏Very nice . love to see more 👍👍videos . 😍😍 thanks for uploading👌👌