{"id":554,"date":"2021-02-26T17:00:49","date_gmt":"2021-02-26T08:00:49","guid":{"rendered":"http:\/\/www.opentone.co.jp\/ot-lab\/?p=554"},"modified":"2025-05-12T10:06:21","modified_gmt":"2025-05-12T01:06:21","slug":"mysql%e3%81%a7%e3%81%aesql%e3%83%81%e3%83%a5%e3%83%bc%e3%83%8b%e3%83%b3%e3%82%b0%e3%81%ab%e3%81%a4%e3%81%84%e3%81%a6%ef%bc%88explain%e3%81%ae%e8%a6%8b%e6%96%b9%ef%bc%89","status":"publish","type":"post","link":"https:\/\/www.opentone.co.jp\/ot-lab\/all\/web-system\/mysql%e3%81%a7%e3%81%aesql%e3%83%81%e3%83%a5%e3%83%bc%e3%83%8b%e3%83%b3%e3%82%b0%e3%81%ab%e3%81%a4%e3%81%84%e3%81%a6%ef%bc%88explain%e3%81%ae%e8%a6%8b%e6%96%b9%ef%bc%89","title":{"rendered":"MySQL\u3067\u306eSQL\u30c1\u30e5\u30fc\u30cb\u30f3\u30b0\u306b\u3064\u3044\u3066\uff08EXPLAIN\u306e\u898b\u65b9\uff09"},"content":{"rendered":"\n<p>\u7686\u3055\u3093\u3001\u3053\u3093\u306b\u3061\u306f\u3002<\/p>\n\n\n\n<p>\u524d\u56de\u3001MySQL\u3067\u30c6\u30fc\u30d6\u30eb\u3092\u4f5c\u6210\u3057\u3066\u3001\u30a2\u30ca\u30e9\u30a4\u30ba\u3059\u308b\u3068\u3053\u308d\u307e\u3067\u5b9f\u65bd\u3057\u307e\u3057\u305f\u306e\u3067\u3001<\/p>\n\n\n\n<p>\u4eca\u56de\u306fEXPLAIN\u3092\u4f7f\u3063\u3066\u3001\u30af\u30a8\u30ea\u306e\u5b9f\u884c\u8a08\u753b\u3092\u78ba\u8a8d\u3057\u3066\u884c\u3053\u3046\u3068\u601d\u3044\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u307e\u305a\u3001\u793e\u54e1\u305d\u308c\u305e\u308c\u306b\u95a2\u308f\u3063\u3066\u3044\u308b\u30d7\u30ed\u30b8\u30a7\u30af\u30c8\u3092\u62bd\u51fa\u3059\u308b\u30af\u30a8\u30ea\u3067\u3001EXPLAIN\u3092\u53d6\u3063\u3066\u307f\u307e\u3057\u305f\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img fetchpriority=\"high\" decoding=\"async\" width=\"848\" height=\"227\" src=\"https:\/\/www.opentone.co.jp\/ot-lab\/wp-content\/uploads\/sites\/11\/2021\/02\/explain11.png\" alt=\"\" class=\"wp-image-555\" srcset=\"https:\/\/www.opentone.co.jp\/ot-lab\/wp-content\/uploads\/sites\/11\/2021\/02\/explain11.png 848w, https:\/\/www.opentone.co.jp\/ot-lab\/wp-content\/uploads\/sites\/11\/2021\/02\/explain11-300x80.png 300w, https:\/\/www.opentone.co.jp\/ot-lab\/wp-content\/uploads\/sites\/11\/2021\/02\/explain11-768x206.png 768w\" sizes=\"(max-width: 848px) 100vw, 848px\" \/><\/figure>\n\n\n\n<p>\u305d\u308c\u305e\u308c\u306e\u9805\u76ee\u306f\u4ee5\u4e0b\u306e\u5185\u5bb9\u3092\u8868\u3057\u3066\u3044\u308b\u3088\u3046\u3067\u3059\u3002<\/p>\n\n\n\n<p>\uff08MySQL\u306e\u30b5\u30a4\u30c8\u306b\u8a18\u8ff0\u3055\u308c\u3066\u3044\u308b\u60c5\u5831\u3060\u3051\u3067\u306f\u7406\u89e3\u3057\u306b\u304f\u3044\u305f\u3081\u3001\u82e5\u5e72\u610f\u8a33\u3057\u3066\u3044\u307e\u3059\u3002\uff09<\/p>\n\n\n\n<p>EXPLAIN\u306e\u8aad\u307f\u65b9<\/p>\n\n\n\n<p>id:<br>\u304a\u305d\u3089\u304f\u3001SUBQUERY\u304c\u767a\u884c\u3055\u308c\u305f\u5834\u5408\u306e\u5165\u308c\u5b50\u306e\u30ec\u30d9\u30eb\u3092\u8868\u3057\u3066\u3044\u308b\u3082\u306e\u3068\u601d\u308f\u308c\u308b\u3002<br>\u30af\u30a8\u30ea\u306f\u3001\u6570\u5b57\u306e\u5c11\u306a\u3044\u3082\u306e\u304b\u3089\u9806\u306b\u8a55\u4fa1\u3059\u308b\u3002<\/p>\n\n\n\n<p>select_type:<br>select\u306e\u7a2e\u985e\u3002<br>\u5b9f\u969b\u306b\u306f\u3001\u767a\u884c\u3057\u305f\u30af\u30a8\u30ea\u306e\u3069\u306e\u30c6\u30fc\u30d6\u30eb\u3092\u53d6\u5f97\u3059\u308bSQL\u304b\u3092<br>\u898b\u5206\u3051\u308b\u76ee\u5370\u304f\u3089\u3044\u306e\u610f\u5473\u5408\u3044\u3057\u304b\u306a\u3055\u305d\u3046\u3002<br>DEPENDENT UNION\u3084DEPENDENT SUBQUERY\u304b\u3089\u306f\u3001<br>\u7d50\u5408\u65b9\u6cd5\u304c\u8aad\u307f\u53d6\u308c\u308b\u304c\u3001\u5f8c\u8ff0\u3059\u308btype\u304c\u3042\u308b\u304b\u3089\u3044\u3089\u306a\u3044\u3088\u3046\u306a\u6c17\u3082\u3059\u308b\u3002<\/p>\n\n\n\n<p>table:<br>\u305d\u306e\u51e6\u7406\u304c\u30a2\u30af\u30bb\u30b9\u3057\u3066\u3044\u308b\u30c6\u30fc\u30d6\u30eb\u3002<\/p>\n\n\n\n<p>partitions:<br>partition\u69cb\u6210\u306e\u30c6\u30fc\u30d6\u30eb\u306e\u5834\u5408\u306b\u3001\u305d\u306e\u51e6\u7406\u304c\u30a2\u30af\u30bb\u30b9\u3057\u3066\u3044\u308bpartition\u3092\u8868\u3059\u3002<\/p>\n\n\n\n<p>type:<br>\u7d50\u5408\u578b\u3092\u8868\u3059\u3002\u4ee5\u4e0b\u3001\u305d\u308c\u305e\u308c\u306e\u7d50\u5408\u578b\u306e\u8868\u3059\u5185\u5bb9\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>system:<br>\u30c6\u30fc\u30d6\u30eb\u304c1\u30ec\u30b3\u30fc\u30c9\u306e\u307f\u3067\u69cb\u6210\u3055\u308c\u308b\u5834\u5408\u3001system\u3068\u306a\u308b\u3002<br>system\u306fconst\u306e\u7279\u6b8a\u306a\u30d1\u30bf\u30fc\u30f3\u3068\u898b\u306a\u305b\u308b\u3002<\/li><li>const:<br>\u6307\u5b9a\u3057\u305f\u6761\u4ef6\u3067\u30c6\u30fc\u30d6\u30eb\u304b\u3089\u53d6\u5f97\u3059\u308b\u30ec\u30b3\u30fc\u30c9\u304c1\u30ec\u30b3\u30fc\u30c9\u306e\u307f\u3068\u306a\u308b\u5834\u5408\u3001<br>\u3053\u306e\u30ec\u30b3\u30fc\u30c9\u306e\u5024\u306f\u30aa\u30d7\u30c6\u30a3\u30de\u30a4\u30b6\u306b\u3088\u3063\u3066\u5b9a\u6570\u3068\u898b\u306a\u3055\u308c\u3001<br>1\u56de\u3057\u304b\u8aad\u307f\u53d6\u3089\u308c\u306a\u3044\u305f\u3081\u3001\u9ad8\u901f\u3002<\/li><li>eq_ref:<br>Oracle\u3067\u8a00\u3046\u3001nested loop join\u306b\u76f8\u5f53\u3059\u308b\u3068\u601d\u308f\u308c\u308b\u3002<br>\u5916\u5074\u306e\u30af\u30a8\u30ea\u3067\u53d6\u5f97\u3057\u305f\u30ec\u30b3\u30fc\u30c9\uff11\u30ec\u30b3\u30fc\u30c9\u305a\u3064\u306b\u5bfe\u3057\u3066\u30011\u30ec\u30b3\u30fc\u30c9\u305a\u3064\u30a2\u30af\u30bb\u30b9\u3059\u308b\u3002<\/li><li>ref:<br>\u3053\u3061\u3089\u306f\u3001nested loop\u3067\u3082\u3001\u5185\u5074\u306e\u30af\u30a8\u30ea\u3068\u306e\u7d50\u5408\u30ad\u30fc\u304cunique\u3067\u306f\u306a\u3044\u5834\u5408\u306b\u4f7f\u7528\u3059\u308b\u7d50\u5408\u5f62\u5f0f\u3002<br>\u5f53\u7136\u3001\u5185\u5074\u306e\u30af\u30a8\u30ea\u3067\u306f\u30ad\u30fc\u306b\u8a72\u5f53\u3059\u308b\u30ec\u30b3\u30fc\u30c9\u304c\u5168\u3066\u53d6\u5f97\u3055\u308c\u308b\u3002<\/li><li>ref_or_null:<br>ref\u306b\u52a0\u3048\u3066\u3001\u7d50\u5408\u30ad\u30fc\u306e\u5024\u304cnull\u306e\u5834\u5408\u306e\u691c\u7d22\u3082\u5b9f\u884c\u3055\u308c\u308b\u3002<\/li><li>index_merge:<br>\u8907\u6570\u306erenge scan\u7d50\u679c\u3092\u7d50\u5408\u3059\u308b\u5834\u5408\u306b\u4f7f\u308f\u308c\u308b\u3089\u3057\u3044\u3002<\/li><li>unique_subquery:<br>\u30b5\u30d6\u30af\u30a8\u30ea\u306e\u8fd4\u5374\u3059\u308b\u5024\u304c1\u30ec\u30b3\u30fc\u30c9\u306e\u5834\u5408\u306b\u4f7f\u7528\u3055\u308c\u308b\u3002<\/li><li>index_subquery:<br>\u30b5\u30d6\u30af\u30a8\u30ea\u306e\u8fd4\u5374\u3059\u308b\u5024\u304c\u8907\u6570\u306e\u5834\u5408\u306b\u4f7f\u7528\u3055\u308c\u308b\u3002<\/li><li>range:<br>\u30a4\u30f3\u30c7\u30c3\u30af\u30b9\u7bc4\u56f2\u691c\u7d22\u306e\u5834\u5408\u306b\u4f7f\u7528\u3002<\/li><li>index:<br>\u30a4\u30f3\u30c7\u30c3\u30af\u30b9\u30c4\u30ea\u30fc\u306b\u5bfe\u3059\u308b\u5168\u4ef6\u691c\u7d22\u3002Oracle\u3067\u8a00\u3046\u3001index full scan\u306b\u76f8\u5f53\u3059\u308b\u3068\u601d\u308f\u308c\u308b\u3002<\/li><li>ALL:<br>\u5168\u8868\u691c\u7d22\u3002Oracle\u3067\u8a00\u3046\u3001full scan\u3002<\/li><\/ul>\n\n\n\n<p>\u30aa\u30f3\u30e9\u30a4\u30f3\u51e6\u7406\u306e\u3088\u3046\u306b\u3001\u3042\u308b\u7279\u5b9a\u306e\u30ec\u30b3\u30fc\u30c9\u3092\u53d6\u5f97\u3057\u3066\u305d\u306e\u30ec\u30b3\u30fc\u30c9\u3092\u66f4\u65b0\u3059\u308b\u3088\u3046\u306a\u51e6\u7406\u7cfb\u3067\u3042\u308c\u3070\u3001<br>\u307e\u305a\u306f&#8221;ALL&#8221;\u3092\u306a\u304f\u3059\u3088\u3046\u306b\u30a4\u30f3\u30c7\u30c3\u30af\u30b9\u3092\u5229\u7528\u3059\u308b\u306e\u304c\u901a\u5e38\u306e\u30c1\u30e5\u30fc\u30cb\u30f3\u30b0\u306b\u306a\u308a\u307e\u3059\u306d\u3002<br>\u305f\u3060\u3001MySQL\u306e\u30b5\u30a4\u30c8\u304b\u3089\u60c5\u5831\u3060\u3051\u3067\u306f\u3001Oracle\u3068\u9055\u3063\u3066\u300c\u305d\u308c\u305e\u308c\u306e\u7d50\u5408\u65b9\u5f0f\u304c\u3069\u306e\u304f\u3089\u3044\u306e\u30b3\u30b9\u30c8\u3092\u98df\u3046\u306e\u304b\u300d\u3042\u308b\u3044\u306f\u3001\u300c\u3069\u306e\u69d8\u306a\u554f\u3044\u5408\u308f\u305b\u3067\u3042\u308c\u3070\u3001\u3069\u306e\u69d8\u306a\u7d50\u5408\u65b9\u5f0f\u306b\u306a\u308c\u3070\u52b9\u7387\u304c\u826f\u3055\u305d\u3046\u304b\u300d\u3068\u8a00\u3063\u305f\u3068\u3053\u308d\u304c\u898b\u3048\u306b\u304f\u3044\u3002<\/p>\n\n\n\n<p>\u6b21\u56de\u306f\u3001EXPLAIN\u3067\u51fa\u529b\u3055\u308c\u308b\u6b8b\u308a\u306e\u60c5\u5831\u306b\u3064\u3044\u3066\u306e\u7814\u7a76\u3068\u3001\u305d\u308c\u305e\u308c\u306e\u7d50\u5408\u51e6\u7406\u306e\u5185\u5bb9\u306b\u3064\u3044\u3066\u8abf\u3079\u3066\u307f\u305f\u3044\u3068\u601d\u3044\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u3068\u8a00\u3046\u308f\u3051\u3067\u3001\u6b21\u56de\u306b\u7d9a\u304f\u3002&nbsp;<\/p>\n<div class=\"opent-_2\" style=\"margin-top: 10px;margin-right: 10px;margin-bottom: 10px;margin-left: 10px;\" id=\"opent-2068590082\"><a href=\"https:\/\/www.opentone.co.jp\/backlog\/\" aria-label=\"twitter_backlogskt_new\"><img src=\"https:\/\/www.opentone.co.jp\/ot-lab\/wp-content\/uploads\/sites\/11\/2023\/02\/twitter_backlogskt_new.jpg\" alt=\"\"  srcset=\"https:\/\/www.opentone.co.jp\/ot-lab\/wp-content\/uploads\/sites\/11\/2023\/02\/twitter_backlogskt_new.jpg 1024w, https:\/\/www.opentone.co.jp\/ot-lab\/wp-content\/uploads\/sites\/11\/2023\/02\/twitter_backlogskt_new-300x157.jpg 300w, https:\/\/www.opentone.co.jp\/ot-lab\/wp-content\/uploads\/sites\/11\/2023\/02\/twitter_backlogskt_new-768x401.jpg 768w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" width=\"384\" height=\"200\"   \/><\/a><\/div>","protected":false},"excerpt":{"rendered":"<p>\u7686\u3055\u3093\u3001\u3053\u3093\u306b\u3061\u306f\u3002 \u524d\u56de\u3001MySQL\u3067\u30c6\u30fc\u30d6\u30eb\u3092\u4f5c\u6210\u3057\u3066\u3001\u30a2\u30ca\u30e9\u30a4\u30ba\u3059\u308b\u3068\u3053\u308d\u307e\u3067\u5b9f\u65bd\u3057\u307e\u3057\u305f\u306e\u3067<\/p>\n","protected":false},"author":1,"featured_media":555,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_uag_custom_page_level_css":"","_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[28],"tags":[8],"class_list":["post-554","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-web-system","tag-blog",""],"acf":[],"aioseo_notices":[],"uagb_featured_image_src":{"full":["https:\/\/www.opentone.co.jp\/ot-lab\/wp-content\/uploads\/sites\/11\/2021\/02\/explain11.png",848,227,false],"thumbnail":["https:\/\/www.opentone.co.jp\/ot-lab\/wp-content\/uploads\/sites\/11\/2021\/02\/explain11-150x150.png",150,150,true],"medium":["https:\/\/www.opentone.co.jp\/ot-lab\/wp-content\/uploads\/sites\/11\/2021\/02\/explain11-300x80.png",300,80,true],"medium_large":["https:\/\/www.opentone.co.jp\/ot-lab\/wp-content\/uploads\/sites\/11\/2021\/02\/explain11-768x206.png",640,172,true],"large":["https:\/\/www.opentone.co.jp\/ot-lab\/wp-content\/uploads\/sites\/11\/2021\/02\/explain11.png",640,171,false],"1536x1536":["https:\/\/www.opentone.co.jp\/ot-lab\/wp-content\/uploads\/sites\/11\/2021\/02\/explain11.png",848,227,false],"2048x2048":["https:\/\/www.opentone.co.jp\/ot-lab\/wp-content\/uploads\/sites\/11\/2021\/02\/explain11.png",848,227,false],"engage-mag-carousel-img":["https:\/\/www.opentone.co.jp\/ot-lab\/wp-content\/uploads\/sites\/11\/2021\/02\/explain11-783x227.png",783,227,true],"engage-mag-carousel-img-landscape":["https:\/\/www.opentone.co.jp\/ot-lab\/wp-content\/uploads\/sites\/11\/2021\/02\/explain11-783x225.png",783,225,true],"engage-mag-carousel-large-img":["https:\/\/www.opentone.co.jp\/ot-lab\/wp-content\/uploads\/sites\/11\/2021\/02\/explain11.png",848,227,false],"engage-mag-carousel-large-img-landscape":["https:\/\/www.opentone.co.jp\/ot-lab\/wp-content\/uploads\/sites\/11\/2021\/02\/explain11.png",848,227,false],"engage-mag-large-thumb":["https:\/\/www.opentone.co.jp\/ot-lab\/wp-content\/uploads\/sites\/11\/2021\/02\/explain11.png",848,227,false],"engage-mag-small-thumb":["https:\/\/www.opentone.co.jp\/ot-lab\/wp-content\/uploads\/sites\/11\/2021\/02\/explain11-350x220.png",350,220,true]},"uagb_author_info":{"display_name":"ah106rx4o4","author_link":"https:\/\/www.opentone.co.jp\/ot-lab\/author\/ah106rx4o4"},"uagb_comment_info":0,"uagb_excerpt":"\u7686\u3055\u3093\u3001\u3053\u3093\u306b\u3061\u306f\u3002 \u524d\u56de\u3001MySQL\u3067\u30c6\u30fc\u30d6\u30eb\u3092\u4f5c\u6210\u3057\u3066\u3001\u30a2\u30ca\u30e9\u30a4\u30ba\u3059\u308b\u3068\u3053\u308d\u307e\u3067\u5b9f\u65bd\u3057\u307e\u3057\u305f\u306e\u3067","_links":{"self":[{"href":"https:\/\/www.opentone.co.jp\/ot-lab\/wp-json\/wp\/v2\/posts\/554","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.opentone.co.jp\/ot-lab\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.opentone.co.jp\/ot-lab\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.opentone.co.jp\/ot-lab\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.opentone.co.jp\/ot-lab\/wp-json\/wp\/v2\/comments?post=554"}],"version-history":[{"count":1,"href":"https:\/\/www.opentone.co.jp\/ot-lab\/wp-json\/wp\/v2\/posts\/554\/revisions"}],"predecessor-version":[{"id":556,"href":"https:\/\/www.opentone.co.jp\/ot-lab\/wp-json\/wp\/v2\/posts\/554\/revisions\/556"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.opentone.co.jp\/ot-lab\/wp-json\/wp\/v2\/media\/555"}],"wp:attachment":[{"href":"https:\/\/www.opentone.co.jp\/ot-lab\/wp-json\/wp\/v2\/media?parent=554"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.opentone.co.jp\/ot-lab\/wp-json\/wp\/v2\/categories?post=554"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.opentone.co.jp\/ot-lab\/wp-json\/wp\/v2\/tags?post=554"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}