How to unload data from a specific table in xml from phpmyadmin?

Question

PHP

There is a site on joomla, you need to upload an xml file to the server, data from the _users table, as I understand it, the easiest way to do this (I may be wrong) is by means of a certain php script. Help solve the problem.

upd and rename columns in exported xml file

Answer 1

in phpmyadmin go to the desired table and on the tab export save to xml

Answer 2

The fact is that this function does not make queries, but compares data with the $wp_taxonomies global variable, which is not defined in functions.php. This function would work in a template file.
To get in functions.php all currently registered taxonomies (there will be a comment below about this selection) use the get_taxonomies() function
there will be data in such a variable and your code will continue to work.
I will also pay attention to the pitfalls of your task.
This variable will initially contain only basic WP taxonomies: category, post_tag, nav_menu, link_category,
post_format taxonomy is connected to the 'init' (!) initialization hook, which is the most correct. And if you registered the taxonomy through a plugin, for example, through the popular Custom post ui, etc. then it will not get here at all, because registration of taxonomies in the plugin occurs before functions.php is triggered