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phpbb3 export Specified Key was Too Long
This discussion is related to the Vanilla Porter addon.

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I think that in the subject field of one or more of your topics, the text is too long. Check the properties of the subject field of the z_pmgroup table (and similar table of phpbb) and report back please
There was an error rendering this rich post.
SELECT * FROM
phpbb_topics
WHERE length(topic_title) > 200 returns 0. the max size of the field is 255.
SELECT * FROM
phpbb_posts
where length(post_subject)>200 also returned zero 0.
where else could I check ?
Find this:
$Ex->Query("create index z_idx_pmgroup on z_pmgroup (subject, userids);");
and comment it out.
The export will probably take longer (potentially FAR longer), but should succeed.
Thank you