{"id":49,"date":"2012-02-19T16:25:46","date_gmt":"2012-02-19T15:25:46","guid":{"rendered":"http:\/\/blog.jeremm.fr\/?p=49"},"modified":"2012-03-20T20:10:59","modified_gmt":"2012-03-20T19:10:59","slug":"accelerez-repair-alter-table-enable-keys","status":"publish","type":"post","link":"https:\/\/blog.jeremm.fr\/?p=49","title":{"rendered":"Acc\u00e9l\u00e9rer repair, alter table (enable keys) MyISAM"},"content":{"rendered":"

Pour ajouter ou activer des indexes sur une table MyISAM, la requ\u00eate peut \u00eatre tr\u00e8s long en fonction du nombre d’indexes.<\/p>\n

Mysql utilise un repair table pour activer les indexes, mais il y a deux fa\u00e7ons :
\n– avec un repair by sorting
\n– avec un repair using keycache (cette fa\u00e7on est tr\u00e8s lente car cr\u00e9e les indexes 1 par 1)<\/p>\n

Mysql utilise ‘repair using keycache’ si :
\n– nombre d’index > myisam_repair_threads
\n– taille de chaque index > myisam_max_sort_file_size<\/p>\n

Augmenter le param\u00e8tre myisam_repair_threads devrait la plus part du temps permettre \u00e0 mysql d’utiliser le repair by sorting<\/p>\n","protected":false},"excerpt":{"rendered":"

Pour ajouter ou activer des indexes sur une table MyISAM, la requ\u00eate peut \u00eatre tr\u00e8s long en fonction du nombre d’indexes. Mysql utilise un repair table pour activer les indexes, mais il y a deux fa\u00e7ons : – avec un repair by sorting – avec un repair using keycache (cette fa\u00e7on est tr\u00e8s lente car […]<\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[5],"tags":[19,15,20],"_links":{"self":[{"href":"https:\/\/blog.jeremm.fr\/index.php?rest_route=\/wp\/v2\/posts\/49"}],"collection":[{"href":"https:\/\/blog.jeremm.fr\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.jeremm.fr\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.jeremm.fr\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.jeremm.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=49"}],"version-history":[{"count":10,"href":"https:\/\/blog.jeremm.fr\/index.php?rest_route=\/wp\/v2\/posts\/49\/revisions"}],"predecessor-version":[{"id":364,"href":"https:\/\/blog.jeremm.fr\/index.php?rest_route=\/wp\/v2\/posts\/49\/revisions\/364"}],"wp:attachment":[{"href":"https:\/\/blog.jeremm.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=49"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.jeremm.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=49"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.jeremm.fr\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=49"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}