{"id":371,"date":"2021-07-28T08:44:39","date_gmt":"2021-07-27T23:44:39","guid":{"rendered":"https:\/\/sumomo.ohwaki.jp\/wordpress\/?p=371"},"modified":"2021-07-28T08:44:39","modified_gmt":"2021-07-27T23:44:39","slug":"linq%e3%81%a7left-outer-join","status":"publish","type":"post","link":"https:\/\/sumomo.ohwaki.jp\/wordpress\/?p=371","title":{"rendered":"LINQ\u3067LEFT OUTER JOIN"},"content":{"rendered":"\n<p>LINQ\u3067\u5916\u90e8\u7d50\u5408(LEFT OUTER JOIN)\u3092\u884c\u3046\u305f\u3081\u306e\u30e1\u30e2\u3002<\/p>\n\n\n\n<p>LINQ\u3067\u5185\u90e8\u7d50\u5408(LEFT INNER JOIN)\u3092\u884c\u3046\u306b\u306f\u3001JOIN\u53e5\u3092\u4f7f\u3063\u3066\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u611f\u3058\u3067\u884c\u3048\u3070\u826f\u3044\u306e\u306f\u826f\u304f\u4f8b\u3082\u51fa\u3066\u3044\u308b\u3057\u3001\u69cb\u6587\u4e0a\u3082\u7d20\u76f4\u306b\u7d0d\u5f97\u3067\u304d\u308b\u3002<br>(\u3061\u306a\u307f\u306b\u3001\u8907\u6570\u30ad\u30fc\u304c\u3042\u308b\u5834\u5408\u306f\u3001<br>new {t1.key1,t1.key2[,&#8230;]} equals new {t2.key1,t2.key2[,&#8230;]}<br>\u306e\u5f62\u3067\u6307\u5b9a\u3059\u308b)<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism undefined-numbers lang-csharp\" data-file=\"Inner Join\" data-lang=\"C#\"><code>\/\/ Collection1\u3068Collection2\u306e[KEY]\u304c\u540c\u3058\u3082\u306e\u3092\u7d50\u5408\n\/\/ \u540c\u3058\u30ad\u30fc\u3092\u542b\u307e\u306a\u3044Collection1\u306f\u96c6\u5408\u304b\u3089\u5916\u3055\u308c\u308b\u3002\nvar q = from t1 in Collection1\n\tjoin t2 in Collection2 on t2.[KEY] equals t1.[KEY]\n\t\u30fb\u30fb\u30fb<\/code><\/pre><\/div>\n\n\n\n<p>\u3067\u306f\u3001\u5916\u90e8\u7d50\u5408(LEFT OUTER JOIN)\u3001\u3064\u307e\u308a\u3001Collection1\u306f\u5168\u3066\u306e\u30ec\u30b3\u30fc\u30c9\u304c\u9078\u629e\u3055\u308c\u3001Collection2\u304c\u5b58\u5728\u3057\u306a\u3044\u5834\u5408\u306f\u3001t2\u3092NULL\u3068\u3059\u308b)\u306b\u306f\u3069\u306e\u3088\u3046\u306b\u8868\u73fe\u3059\u308b\u306e\u304c\u4e00\u756a\u7c21\u5358\u304b?<\/p>\n\n\n\n<p>\u7b54\u3048\u306f\u610f\u5916\u306a\u3082\u306e\u3067\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u30af\u30a8\u30ea\u3092\u7528\u3044\u308b\u3053\u3068\u3067\u304b\u306a\u308a\u7c21\u5358\u306b\u5b9f\u88c5\u53ef\u80fd\u3067\u3042\u308b\u3002<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism undefined-numbers lang-csharp\" data-file=\"Outer Join\" data-lang=\"C#\"><code>\/\/ Collection1\u3068Collection2\u306e[KEY]\u304c\u540c\u3058\u3082\u306e\u3092\u7d50\u5408\n\/\/ \u305f\u3060\u3057\u3001Collection2\u3068\u540c\u3058\u30ad\u30fc\u3092\u6301\u3063\u3066\u3044\u306a\u3044Collection1\u3082\u96c6\u5408\u306b\u542b\u3081\u308b\nvar q = from t1 in Collection1\n\t\tfrom t2 in Collection2.Where(c=&gt;c.[KEY] == t1.[KEY]).DefaultIfEmpty()\n\t\u30fb\u30fb\u30fb<\/code><\/pre><\/div>\n\n\n\n<p>1\u3064\u306e\u30af\u30a8\u30ea\u4e2d\u306bfrom\u53e5\u30922\u56de\u4f7f\u7528\u3057\u3066\u30012\u3064\u76ee\u306e\u96c6\u5408\u306f1\u3064\u3081\u306e\u30ad\u30fc\u3067\u7d5e\u8fbc\u3092\u304b\u3051\u3001\u3055\u3089\u306b\u3001\u305d\u306e\u30ad\u30fc\u3092\u6301\u3064\u30ec\u30b3\u30fc\u30c9\u304c\u5b58\u5728\u3057\u306a\u3044\u5834\u5408\u306b\u306f\u30c7\u30d5\u30a9\u30eb\u30c8\u5024(null)\u3092\u8fd4\u3059\u3088\u3046\u306b\u3059\u308b\u3002<\/p>\n\n\n\n<p>\u3064\u3044\u6700\u8fd1\u307e\u3067\u3001from\u53e5\u30922\u56de\u4ee5\u4e0a\u3001\u4f7f\u7528\u3067\u304d\u308b\u306e\u77e5\u3089\u306a\u304b\u3063\u305f\u30fb\u30fb\u30fb<\/p>\n","protected":false},"excerpt":{"rendered":"<p>LINQ\u3067\u5916\u90e8\u7d50\u5408(LEFT OUTER JOIN)\u3092\u884c\u3046\u305f\u3081\u306e\u30e1\u30e2\u3002 LINQ &hellip; <a href=\"https:\/\/sumomo.ohwaki.jp\/wordpress\/?p=371\">\u7d9a\u304d\u3092\u8aad\u3080 <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[18,9,21,4],"tags":[],"class_list":["post-371","post","type-post","status-publish","format-standard","hentry","category-net","category-c","category-linq","category-4"],"_links":{"self":[{"href":"https:\/\/sumomo.ohwaki.jp\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/371","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sumomo.ohwaki.jp\/wordpress\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/sumomo.ohwaki.jp\/wordpress\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/sumomo.ohwaki.jp\/wordpress\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/sumomo.ohwaki.jp\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=371"}],"version-history":[{"count":2,"href":"https:\/\/sumomo.ohwaki.jp\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/371\/revisions"}],"predecessor-version":[{"id":373,"href":"https:\/\/sumomo.ohwaki.jp\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/371\/revisions\/373"}],"wp:attachment":[{"href":"https:\/\/sumomo.ohwaki.jp\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=371"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/sumomo.ohwaki.jp\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=371"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/sumomo.ohwaki.jp\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=371"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}