Is using upgrader_process_complete the correct way to perform plugin updates?

Question

A couple months ago, I got my first WP plugin in the WP plugin repo. The plugin uses register_activation_hook with an attached function to create some custom MySQL tables to store data.

Now that I'm adding some new features, I need to run some ALTER TABLE table_name ADD new_column queries to add some new columns to the tables (for existing plugin installations).

I'm guessing I should use the upgrader_process_complete hook to run the ALTER TABLE queries?

I'm also guessing I will need to start storing the current plugin version number in the database using update_option('my_plugin_version') and get_option('my_plugin_version') to compare the installed plugin version and the current version available ?

Should I always have the current table structure used, ie:

   $sql= "CREATE TABLE " . $table_name . " (
      `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
      `field1` text NOT NULL,      
      `field2` text NOT NULL,
      `field3` text NULL,
      PRIMARY KEY  (`id`)
    ) $charset_collate;";

in the register_activation_hook and not just keeping the original table structure, then checking the version to apply the appropriate tables updates for each version number?

Answer 1

I guess WordPress' codex article is the way to go https://codex.wordpress.org/Creating_Tables_with_Plugins

and from other articles I've read, upgrader_process_complete is usually used to detect when other plugins are updated.