Summary: Make page_len index actually useful so
                    Special:Longpages and Special:Shortpages will be
           Product: MediaWiki
           Version: 1.18-svn
          Platform: All
        OS/Version: All
            Status: NEW
          Severity: enhancement
          Priority: Normal
         Component: Database

Presumably in an attempt to optimize Special:(Long|Short)pages, a page_len
index was introduced in version 1.5 (according to a comment I found). However,
because the query these special pages do is something like SELECT stuff FROM
page WHERE page_namespace IN (content namespaces) AND page_is_redirect=0 ORDER
BY page_len (ASC|DESC) , an index on page_len alone doesn't suffice.

For Longpages it's arguably good enough, since the WHERE clause is gonna be
true for almost all of the 50/100/500/whatever longest pages. For Shortpages,
however, the opposite is true.

In order to fix this properly, we'd have to extend the index of (page_len) to
cover (page_len, page_is_redirect, ppage_namespace) so the WHERE clause is
fully indexed. Any existing legitimate uses of the page_len index (are there
any?) will continue to work because page_len will still be the first field in
the index.

I'll attach a patch shortly.

Configure bugmail:
------- You are receiving this mail because: -------
You are the assignee for the bug.
You are on the CC list for the bug.

Wikibugs-l mailing list

Reply via email to