> But I think it is axiom: less data and shorter keys -> more speed to SELECT.
Sure, but the question is by how much. It doesn't matter that the look up is fast if it gives the wrong result. So its a trade off between accuracy and speed - and in this case I think accuracy takes priority. Dan Osipov Calkins Media http://danosipov.com/blog/ Dmitry Martynenko wrote: > Hi Dan, > > DO> I think the 32 char value must be used, to prevent collisions and > DO> guarantee (almost) the uniqueness. How slow does it make the table > DO> seeks? And what table are we talking about - I think > DO> tx_realurl_chashcache only looks up by spurl_hash. > > I write yesterday about it in another thread, quotation below. > > ----------------------------------------------------------------- > Our server begun to increase time for all SQL queries and > I try to log slow queries (> 100 ms) from class.t3lib_db.php > > Most of them was like: > SELECT /*! SQL_NO_CACHE */ content > FROM tx_realurl_urlencodecache > WHERE url_hash='43d5475f5d7dc35690cb8ab3d7683679' AND tstamp>1232035875 > > This table has more then 450 000 records. > It's index size greater than 30 Mb. > I think big index size and long key length take lot of time to search. > ----------------------------------------------------------------- > > May be it is need more testing. > But I think it is axiom: less data and shorter keys -> more speed to SELECT. > _______________________________________________ TYPO3-english mailing list TYPO3-english@lists.netfielders.de http://lists.netfielders.de/cgi-bin/mailman/listinfo/typo3-english