Hi there, about how to add a extra field to category

I need to add a field to the category, which needs to support multiple languages like the category name. But I have tried many times without success, can anyone help me see what is wrong with my code?
A total of 5 changes have been made in my code, and they are all marked.
thank you very much

Can you explain more clearly what is the problem you are trying to solve?

Thank you for you reply.
I just want another field likes category name, I have already inserted a sql of the extra field in my database. But these is something wrong with my code on categories.php.

I just want another field likes category name
Why - for what purpose? You mentioned multiple languages so I suspect you are attempting to do something unnecessary....but you need to explain.

Sorry for not being clear, my target market is Japan, and I am selling curtains.
So I don't want Japanese categories or product names to be used for my urls， that looks very long and the URL looks weird when opened.
So my purpose is that the original category name is only used for my category URLs, such as Curtains-c-1.html
And the fields I need, such as categories_name2, will be used for Japanese category names, such as: カーテン.
This way I avoid the Japanese category name being used for the url and achieve pure English category urls.
To sum it up, I would like to have another category name 2, the original "categories_name" for the URL and another categories_name2(let's say this name) for the japanese category name.

The plugin "Ceon URI Mapping (SEO) v5" perfectly solved my problem, no longer need to add the extra field to my categories now.
:hug:Thank you all.

morrysmith:

The plugin "Ceon URI Mapping (SEO) v5" perfectly solved my problem, no longer need to add the extra field to my categories now.
:hug:Thank you all.

If your site has been in operation for a period of time to have been indexed, be sure that you have your previous URIs logged as non active (or retained as your current URI) so that you don't lose the references to your product from the internet.

Thank you for your reminder.
But I can't solve the code problem myself, otherwise I'd still be inclined to add an extra categories name field to solve my problem.:D