+/**
+ * Execute changes made in WordPress 4.2.0.
+ *
+ * @since 4.2.3
+ */
+function upgrade_423() {
+ global $wp_current_db_version, $wpdb;
+
+ if ( $wp_current_db_version < 31536 && $wpdb->charset === 'utf8mb4' ) {
+ if ( is_multisite() ) {
+ $tables = $wpdb->tables( 'blog' );
+ } else {
+ $tables = $wpdb->tables( 'all' );
+ if ( defined( 'DO_NOT_UPGRADE_GLOBAL_TABLES' ) ) {
+ $global_tables = $wpdb->tables( 'global' );
+ $tables = array_diff_assoc( $tables, $global_tables );
+ }
+ }
+
+ foreach ( $tables as $table ) {
+ maybe_convert_table_to_utf8mb4( $table );
+ }
+ }
+}
+