Somehow I messed up one of my forums and had it parenting itself, all the forums listed below then got messed up as I tried to correct the problem. I get this error when I try to move a forum out from under the parent forum to have no parent:
General Error
SQL ERROR [ mysqli ]
You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'AND right_id >' at line 4 [1064]
SQL
UPDATE phpbb_forums SET right_id = right_id - 2, forum_parents = '' WHERE left_id < AND right_id >
BACKTRACE
FILE: includes/db/mysqli.php
LINE: 125
CALL: dbal->sql_error()
FILE: includes/acp/acp_forums.php
LINE: 1234
CALL: dbal_mysqli->sql_query()
FILE: includes/acp/acp_forums.php
LINE: 1162
CALL: acp_forums->move_forum()
FILE: includes/acp/acp_forums.php
LINE: 159
CALL: acp_forums->update_forum_data()
FILE: includes/functions_module.php
LINE: 463
CALL: acp_forums->main()
FILE: adm/index.php
LINE: 74
CALL: p_master->load_active()