Problem with queries related to polylang which break down my site

Hi there.
I got a problem with my site, which I guess is related with some implementation of Polylang, or the way Polylang treats translations.

My site has 550 posts, which are translated to 3 languages.
It’s a site I have received for maintenance and I have no contact with the former developer.

The problem is a huge massive sql 88K very slow query, that takes 1-2 seconds and runs with every user session, and when number of simultaneously users passing 10, the database gets locked up, and all the site crushes down.

It’s a nightmare.

The problematic query is:

SELECT t.*, tt.*
FROM wp_terms AS t
INNER JOIN wp_term_taxonomy AS tt
ON t.term_id = tt.term_id
WHERE tt.taxonomy IN ('post_translations')
AND tt.count > 0
ORDER BY t.name ASC

Which returns 89008 rows…..

Query Monitor identified the Caller like that:

WP_Term_Query->get_terms()
// wp-includes/class-wp-term-query.php:759

WP_Term_Query->query()
// wp-includes/class-wp-term-query.php:301

get_terms()
// wp-includes/taxonomy.php:1237

rb_ext_VC_Config->extend_shortcodes()
// wp-content/themes/setech/vc/rb_vc_config.php:104

do_action('init')
//wp-includes/plugin.php:484

How do I know its related to Polylang?
1. When I disable polylang, the query doesn’t execute anymore.
2. I got 89K post_translations key values, inside “wp_term_taxonomy”.

An example of post translations which repeats 89K times in my database:
a:3:{s:2:"pt";i:63868;s:2:"es";i:7833;s:2:"en";i:7876;}

Questions/doubts
1. Any idea why I get a query this large? Is it a bad implementation of the plugin?
2. Does post translation make sense to you? this amount of information?
3. Why does the query I mentioned at the start of this post need to return 88K results? Does it make any sense?

Reference: Discussion on the subject, including print-screens, on SO

• This topic was modified 2 years, 9 months ago by Shlomi.
• This topic was modified 2 years, 9 months ago by Shlomi.
• This topic was modified 2 years, 9 months ago by Shlomi.