I just noticed one more thing: If I set the "Posts per page" option to more than 130, the topics wont load, it would just refresh the forums listing page, much like the "Select for merge" link does. Maybe, when trying to merge the threads, it tries to load more than this 130 post limit, and fails in doing so??
Edit: Yes, I have confirmed this, if trying to merge two smaller threads (one with 17 posts and one with 10), the third pic comes up.
Edit2: I just ran this command in phpMyAdmin which I created:
Code: Select all
UPDATE phpbb_posts SET `topic_id` = 2 WHERE `topic_id` = 509
Where topic 2 is the destination topic wiht 55k posts, and topic 509 is the source topic, with 8.5k posts. Then I truncated the phpbb_topics table and rebuilt it with the topics_rebuild.php script I found somewhere on here. It succefully merged the threads with no issues. Maybe topic merges should be done in this way instead of trying to load all posts?