backlogs/redmine_backlogs — pull request #566 by cedriclombardot (2012-05-24 08:58:06+00:00)
Title: Fix migration to allow big tables migrations

Fix error

````
Mysql::Error: The SELECT would examine more than MAX_JOIN_SIZE rows; check your WHERE and use SET SQL_BIG_SELECTS=1 or SET SQL_MAX_JOIN_SIZE=# if the SELECT is okay: insert into backlogs_tmp_issue_position
```

when migrate big redmines