Ability to define a cache version only based on country, and not a region, city, etc.
Improve website performance by decreasing the number of different versions.
In my case, i was able to define v=[country_code] which is more URL friendly.
This commit removes the `ORDER BY option_id` part of the query to remove the version transients from the `wp_options` table. This change should help users having performance issues with this query (see for example #21215) and, as far as I can see, ordering is not necessary in this context.
Removing the `ORDER BY` from the query means that MySQL won't have to use filesort:
```
MySQL [wccore]> explain DELETE FROM wp_options WHERE option_name LIKE '\\_transient\\_%1510258328' ORDER BY option_id LIMIT 1000;
+----+-------------+------------+------------+-------+---------------+-------------+---------+-------+------+----------+-----------------------------+
| id | select_type | table | partitions | type | possible_keys | key | key_len | ref | rows | filtered | Extra |
+----+-------------+------------+------------+-------+---------------+-------------+---------+-------+------+----------+-----------------------------+
| 1 | DELETE | wp_options | NULL | range | option_name | option_name | 766 | const | 67 | 100.00 | Using where; Using filesort |
+----+-------------+------------+------------+-------+---------------+-------------+---------+-------+------+----------+-----------------------------+
1 row in set (0.02 sec)
MySQL [wccore]> explain DELETE FROM wp_options WHERE option_name LIKE '\\_transient\\_%1510258328' LIMIT 1000;
+----+-------------+------------+------------+-------+---------------+-------------+---------+-------+------+----------+-------------+
| id | select_type | table | partitions | type | possible_keys | key | key_len | ref | rows | filtered | Extra |
+----+-------------+------------+------------+-------+---------------+-------------+---------+-------+------+----------+-------------+
| 1 | DELETE | wp_options | NULL | range | option_name | option_name | 766 | const | 67 | 100.00 | Using where |
+----+-------------+------------+------------+-------+---------------+-------------+---------+-------+------+----------+-------------+
1 row in set (0.00 sec)
```
Third-party code can set the limit of transients to be deleted to 0 using the filter `woocommerce_delete_version_transients_limit`. If this happens, the code shouldn't schedule a cron event to delete more transients to avoid flooding the list of cron jobs.
Fixes#19890
* wp hook is too late to fire the nocache_headers filter, some caching plugins read it before that it seems.
* Create do_not_cache_page helper function and call that instead of nocache_headers
* Must add checks to prevent caching on certain pages as well
* Nothing to return
Wordpress function get_queried_object_id() returns conflicting IDs
for pages and product category archives which in current
implementation results in product category archives possibly not
being cached if their tag ID conflicts with Woocommerce's special
page IDs - cart, checkout, etc.
Let's switch to implementation using is_page() to address this.
If is_blog_installed() is false then skip some installation steps that
are performed on the 'init' action and which require the database to be
available
* i18n: Remove some HTML tags from translation strings
* i18n: simpler translation string
* i18n: translations strings with surrounding `<strong>` HTML tags should be moved outside the translation string
* i18n: Avoide using `<code>' HTML tags in translation strings
* i18n: Split the notice to avoide using HTML tags in translation strings