1. Editer le fichier my.ini
2. Augmenter la taille du buffer mémoire (attention à ne pas dépasser 80% de la mémoire disponible)
# InnoDB, unlike MyISAM, uses a buffer pool to cache both indexes and # row data. The bigger you set this the less disk I/O is needed to # access data in tables. On a dedicated database server you may set this # parameter up to 80% of the machine physical memory size. Do not set it # too large, though, because competition of the physical memory may # cause paging in the operating system. Note that on 32bit systems you # might be limited to 2-3.5G of user level memory per process, so do not # set it too high. #innodb_buffer_pool_size=47M innodb_buffer_pool_size=512M
Résultat pour la même requète :
Avant
12:43:19 SELECT co.Name, (SELECT MAX(ci.Population) FROM city_huge ci WHERE ci.CountryCode = co.Code) FROM country_huge co 239 row(s) returned 354.297 sec / 0.000 sec
Aprés
12:52:00 SELECT co.Name, (SELECT MAX(ci.Population) FROM city_huge ci WHERE ci.CountryCode = co.Code) FROM country_huge co 239 row(s) returned 4.516 sec / 0.000 sec