WordPress at a glance
function is not described

upgrade_290() WP 2.9.0

Execute changes made in WordPress 2.9.

  • Global. Int. $wp_current_db_version

No Hooks.

Return

Nothing (null).

Usage

upgrade_290();

Code of upgrade 290: wp-admin/includes/upgrade.php WP 5.2.2

<?php
function upgrade_290() {
	global $wp_current_db_version;

	if ( $wp_current_db_version < 11958 ) {
		// Previously, setting depth to 1 would redundantly disable threading, but now 2 is the minimum depth to avoid confusion
		if ( get_option( 'thread_comments_depth' ) == '1' ) {
			update_option( 'thread_comments_depth', 2 );
			update_option( 'thread_comments', 0 );
		}
	}
}