WPML 4.7.1 – WordPress Database Error "Too Many Tables"

Resolved

Reported for: WPML Multilingual CMS 4.7.0

Resolved in: WPML 4.7.2

Overview of the issue

In WPML 4.7.0 and WPML 4.7.1, if a large number of languages are active, the Translation Management plugin does not load due to a database error:

«WordPress database error: Too many tables; MySQL can only use 61 tables in a join for query»

WordPress database error Too many tables; MySQL can only use 61 tables in a join for query 
      SELECT p.post_type 
      FROM wp_posts p
      INNER JOIN wp_icl_translations source_t
        ON source_t.element_id = p.ID
          AND source_t.element_type = CONCAT('post_', p.post_type)
          AND source_t.language_code = 'en'
        LEFT JOIN wp_icl_translations target_t_sq
          ON target_t_sq.trid = source_t.trid
              AND target_t_sq.language_code = 'sq'
        LEFT JOIN wp_icl_translation_status target_ts_sq
          ON target_ts_sq.translation_id = target_t_sq.translation_id
... etc for all languages

This issue prevents Translation Management from functioning correctly.

Workaround

Our development team is actively investigating this issue. In the meantime, you can rollback to the previous version as a temporary solution:

Alternatively, you can remove a few languages in «WPML > Languages.»