What is the problem with MySQL query?

Question

PHP

When entering the data received from the form into MySQL, only one value is inserted into all fields (category ID) obtained from $_POST['categoryId'].

Answer 1

clear

Answer 2

Do you think anyone can answer your question?

Answer 3

I didn't understand anything at all)

Answer 4

An error occurred while generating the request. Most likely, in the condition, where the value is <select>assigned to a variable for insertion into VALUES (), the dot before the equal sign is missing and assignment occurs, not addition.
Other assumptions are strictly by providing source code.

Answer 5

It happens :)