Wikimedia Bugzilla is closed!

Affected system:
    * MediaWiki: 1.11.0 (r29485)
    * PHP: 5.2.5 (apache2handler)
    * PostgreSQL: PostgreSQL 8.2.5 on i686-pc-mingw32, compiled by GCC gcc.exe (GCC) 3.4.2 (mingw-special) 

MOR:
    1) This doesn't seem to happen on a mediawiki running on mySQL.
    2) Enter any text in the search query field. Confirm that the search works as intended.
    3) Now, prepend a minus sign (0x2D) and press either 'Go' or 'Search'.

Additional notes:
  Our installation is slightly modified due to bugs 12365, 12522, 9417.

The error, as reported by mediawiki is:
 Internal error
 
 A database error has occurred Query: SELECT page_id, page_namespace, page_title, rank(titlevector, to_tsquery('default','! byebyelotsofcake'), 1) AS score FROM page p, revision r, pagecontent c WHERE p.page_latest = r.rev_id AND r.rev_text_id = c.old_id AND titlevector @@ to_tsquery('default','! byebyelotsofcake') AND page_is_redirect = 0 AND page_namespace IN (0) ORDER BY score DESC, page_id DESC LIMIT 20 OFFSET 0 Function: Error: 1 ERROR: Query requires full scan, GIN doesn't support it
 
 Backtrace:
 
 #0 D:\wiki\wiki\includes\Database.php(779): DatabasePostgres->reportQueryError('ERROR: Query r...', 1, 'SELECT page_id,...', '', false)
 #1 D:\wiki\wiki\includes\SearchPostgres.php(40): Database->query('SELECT page_id,...')
 #2 D:\wiki\wiki\includes\SpecialSearch.php(157): SearchPostgres->searchTitle('-byebyelotsofca...')
 #3 D:\wiki\wiki\includes\SpecialSearch.php(38): SpecialSearch->showResults('-byebyelotsofca...')
 #4 D:\wiki\wiki\includes\SpecialPage.php(653): wfSpecialSearch(NULL, Object(SpecialPage))
 #5 D:\wiki\wiki\includes\SpecialPage.php(459): SpecialPage->execute(NULL)
 #6 D:\wiki\wiki\includes\Wiki.php(201): SpecialPage::executePath(Object(Title))
 #7 D:\wiki\wiki\includes\Wiki.php(45): MediaWiki->initializeSpecialCases(Object(Title), Object(OutputPage), Object(WebRequest))
 #8 D:\wiki\wiki\index.php(89): MediaWiki->initialize(Object(Title), Object(OutputPage), Object(User), Object(WebRequest))
 #9 {main}