{"id":6881,"date":"2025-02-08T10:42:15","date_gmt":"2025-02-08T01:42:15","guid":{"rendered":"https:\/\/www.chihayafuru.jp\/tech\/?p=6881"},"modified":"2025-12-07T18:43:42","modified_gmt":"2025-12-07T09:43:42","slug":"%e3%82%bd%e3%83%95%e3%83%88%e3%82%a6%e3%82%a7%e3%82%a2%e3%81%ab%e3%81%8a%e3%81%91%e3%82%8b%e3%80%8c%e3%81%aa%e3%81%84%e3%80%8d","status":"publish","type":"post","link":"https:\/\/www.chihayafuru.jp\/tech\/index.php\/archives\/6881","title":{"rendered":"\u30bd\u30d5\u30c8\u30a6\u30a7\u30a2\u306b\u304a\u3051\u308b\u300c\u306a\u3044\u300d"},"content":{"rendered":"<h3>C\u8a00\u8a9e<\/h3>\n<ul>\n<li><code>'\\0'<\/code> : \u30ca\u30eb\u6587\u5b57\u3002 \u7d42\u7aef\u6587\u5b57\u3002 ASCII\u6587\u5b57\u306eNUL\u3002<\/li>\n<li><code>NULL<\/code> : \u30ca\u30eb \u30dd\u30a4\u30f3\u30bf\u3002\u3044\u304b\u306a\u308b\u30a2\u30c9\u30ec\u30b9\u3082\u6307\u3057\u3066\u3044\u306a\u3044\u3053\u3068\u3092\u8868\u3059\u3002<\/li>\n<\/ul>\n<p><!--more--><\/p>\n<h3>Java<\/h3>\n<ul>\n<li><code>\"\"<\/code> : \u9577\u3055\u30bc\u30ed\u306e\u6587\u5b57\u5217\u3002<\/li>\n<li><code>null string<\/code> : \u7121\u52b9\u306a\u30aa\u30d6\u30b8\u30a7\u30af\u30c8(NULL)\u3092\u53c2\u7167\u3057\u3066\u3044\u308bString\u30af\u30e9\u30b9\u5909\u6570\u3002<\/li>\n<\/ul>\n<h3>Objective-C<\/h3>\n<ul>\n<li><code>nil<\/code> : id\u578b(\u6c4e\u7528)\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u304c\u672a\u521d\u671f\u5316\u3067\u3042\u308b\u3053\u3068\u3092\u8868\u3059\u3002<\/li>\n<li><code>Nil<\/code> : null\u30af\u30e9\u30b9\u306e\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3002<\/li>\n<li><code>NULL<\/code> : \u30ca\u30eb \u30dd\u30a4\u30f3\u30bf\u3002C\u8a00\u8a9e\u306e\u4e92\u63db\u3002<\/li>\n<li><code>NSNull<\/code> : \u7a7a\u3092\u610f\u5473\u3059\u308b\u30b7\u30f3\u30b0\u30eb\u30c8\u30f3 \u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3002<\/li>\n<\/ul>\n<h3>SQL (\u30ea\u30ec\u30fc\u30b7\u30e7\u30ca\u30eb\u30fb\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9)<\/h3>\n<p>\uff13\u5024\u8ad6\u7406(True, False, NULL)\u306b\u304a\u3051\u308bNULL\u3002\u7a7a\u5024\u3002<\/p>\n<ul>\n<li>\u4e0d\u660e (Unknown) : \u30b5\u30f3\u30b0\u30e9\u30b9\u3092\u304b\u3051\u305f\u4eba\u306e\u76ee\u306e\u8272\uff08\u30b5\u30f3\u30b0\u30e9\u30b9\u3092\u304b\u3051\u3066\u3044\u308b\u304b\u3089\u76ee\u306e\u8272\u306f\u5206\u304b\u3089\u306a\u3044\uff09\u3002\u672a\u5165\u529b\u306e\u58f2\u4e0a\u9ad8\uff08\u5024\u306f\u78ba\u5b9a\u3057\u3066\u3044\u308b\u304c\u30c7\u30fc\u30bf\u304c\u6b20\u640d\u3057\u3066\u3044\u308b\uff09\u3002<\/li>\n<li>\u672a\u78ba\u5b9a (Uncertain) : \u672a\u6765\u306e\u58f2\u4e0a\u9ad8\uff08\u307e\u3060\u8ab0\u306b\u3082\u5206\u304b\u3089\u306a\u3044\uff09\u3002<\/li>\n<li>\u4e0d\u80fd (Not Applicable) : \u6cd5\u4eba\u306e\u6027\u5225\uff08\u6cd5\u4eba\u306b\u6027\u5225\u306f\u306a\u3044\u3002\u6cd5\u4eba\u306e\u6027\u5225\u3092\u554f\u3046\u3053\u3068\u304c\u7121\u610f\u5473\u3067\u3042\u308b\u3002\uff09\u3002<\/li>\n<\/ul>\n<h3>Microsoft EXCEL<\/h3>\n<ul>\n<li><code>#N\/A<\/code> : Not Applicable\uff08\u8a72\u5f53\u306a\u3057\uff09\u3002LOOKUP\u30ef\u30fc\u30af\u30b7\u30fc\u30c8\u95a2\u6570\u306a\u3069\u3067\u8a72\u5f53\u3059\u308b\u53c2\u7167\u5024\u304c\u898b\u3064\u304b\u3089\u306a\u3044\u3068\u304d\u306e\u5024\u3002<\/li>\n<li><code>#VALUE!<\/code> : \u5024\u3067\u306f\u306a\u3044\u3002\u5f0f\u304c\u6570\u5024\u6f14\u7b97\u4e0d\u80fd\u306a\u5024\uff08\u6587\u5b57\u5217\u306a\u3069\uff09\u3092\u53c2\u7167\u3057\u3066\u3044\u305f\u3002\u6587\u5b57\u5217\u304b\u3089\u6570\u5024\u306b\u5909\u63db\u3059\u308b\u95a2\u6570\u306b\u304a\u3044\u3066\u3001\u6570\u5024\u306b\u5909\u63db\u3067\u304d\u306a\u304b\u3063\u305f\uff08\u6587\u5b57\u5217\u306b\u6570\u5024\u3078\u306e\u5909\u63db\u304c\u4e0d\u80fd\u306a\u6587\u5b57\u304c\u542b\u307e\u308c\u3066\u3044\u305f\uff09\u3002\u306a\u3069\u3002<\/li>\n<li><code>#DIV\/0!<\/code> : \u30bc\u30ed\u9664\u7b97<\/li>\n<\/ul>\n<h3>Ruby<\/h3>\n<dt>\n<dd>nil<\/dd>\n<dl>NilClass\u30af\u30e9\u30b9\u306e\u552f\u4e00\u306e\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3002 false\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3068\u3068\u3082\u306b\u507d\u3067\u3042\u308b\u3053\u3068\u3092\u8868\u3059\u3002<\/dl>\n<\/dt>\n<h3>N\/A<\/h3>\n<ul>\n<li>Not Applicable : \u8a72\u5f53\u306a\u3057<\/li>\n<li>Not Available : \u5229\u7528\u4e0d\u53ef<\/li>\n<li>No Answer : \u7121\u56de\u7b54<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>C\u8a00\u8a9e &#8216;\\0&#8217; : \u30ca\u30eb\u6587\u5b57\u3002 \u7d42\u7aef\u6587\u5b57\u3002 ASCII\u6587\u5b57\u306eNUL\u3002 NULL : \u30ca\u30eb \u30dd\u30a4\u30f3\u30bf\u3002\u3044\u304b\u306a\u308b\u30a2\u30c9\u30ec\u30b9\u3082\u6307\u3057\u3066\u3044\u306a\u3044\u3053\u3068\u3092\u8868\u3059\u3002<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[],"class_list":["post-6881","post","type-post","status-publish","format-standard","hentry","category-memo"],"_links":{"self":[{"href":"https:\/\/www.chihayafuru.jp\/tech\/index.php\/wp-json\/wp\/v2\/posts\/6881","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.chihayafuru.jp\/tech\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.chihayafuru.jp\/tech\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.chihayafuru.jp\/tech\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.chihayafuru.jp\/tech\/index.php\/wp-json\/wp\/v2\/comments?post=6881"}],"version-history":[{"count":36,"href":"https:\/\/www.chihayafuru.jp\/tech\/index.php\/wp-json\/wp\/v2\/posts\/6881\/revisions"}],"predecessor-version":[{"id":8227,"href":"https:\/\/www.chihayafuru.jp\/tech\/index.php\/wp-json\/wp\/v2\/posts\/6881\/revisions\/8227"}],"wp:attachment":[{"href":"https:\/\/www.chihayafuru.jp\/tech\/index.php\/wp-json\/wp\/v2\/media?parent=6881"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.chihayafuru.jp\/tech\/index.php\/wp-json\/wp\/v2\/categories?post=6881"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.chihayafuru.jp\/tech\/index.php\/wp-json\/wp\/v2\/tags?post=6881"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}