{"id":1263,"date":"2025-03-24T08:52:28","date_gmt":"2025-03-23T23:52:28","guid":{"rendered":"https:\/\/dexall.co.jp\/articles\/?p=1263"},"modified":"2025-03-24T08:52:28","modified_gmt":"2025-03-23T23:52:28","slug":"ruby%e3%81%a7%e6%97%a5%e4%bb%98%e5%87%a6%e7%90%86%e3%82%92%e5%ae%8c%e5%85%a8%e3%83%9e%e3%82%b9%e3%82%bf%e3%83%bc%ef%bc%81%e7%8f%be%e5%a0%b4%e3%81%a7%e4%bd%bf%e3%81%88%e3%82%8b%e5%ae%9f%e8%b7%b5","status":"publish","type":"post","link":"https:\/\/dexall.co.jp\/articles\/?p=1263","title":{"rendered":"Ruby\u3067\u65e5\u4ed8\u51e6\u7406\u3092\u5b8c\u5168\u30de\u30b9\u30bf\u30fc\uff01\u73fe\u5834\u3067\u4f7f\u3048\u308b\u5b9f\u8df5\u30ac\u30a4\u30c92024\u5e74\u7248"},"content":{"rendered":"\n<div class=\"toc\"><br \/>\n<b>Warning<\/b>:  Undefined array key \"is_admin\" in <b>\/home\/xs392991\/dexall.co.jp\/public_html\/articles\/wp-content\/themes\/sango-theme\/library\/gutenberg\/dist\/classes\/Toc.php<\/b> on line <b>116<\/b><br \/>\n<br \/>\n<b>Warning<\/b>:  Undefined array key \"is_category_top\" in <b>\/home\/xs392991\/dexall.co.jp\/public_html\/articles\/wp-content\/themes\/sango-theme\/library\/gutenberg\/dist\/classes\/Toc.php<\/b> on line <b>121<\/b><br \/>\n<br \/>\n<b>Warning<\/b>:  Undefined array key \"is_top\" in <b>\/home\/xs392991\/dexall.co.jp\/public_html\/articles\/wp-content\/themes\/sango-theme\/library\/gutenberg\/dist\/classes\/Toc.php<\/b> on line <b>128<\/b><br \/>\n    <div id=\"toc_container\" class=\"sgb-toc--bullets js-smooth-scroll\" data-dialog-title=\"\u76ee\u6b21\">\n      <p class=\"toc_title\">\u76ee\u6b21 <\/p>\n      <ul class=\"toc_list\">  <li class=\"first\">    <a href=\"#i-0\">Ruby\u3067\u306e\u65e5\u4ed8\u51e6\u7406\u306e\u57fa\u790e\u77e5\u8b58<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-1\">Date\u3068DateTime\u30af\u30e9\u30b9\u306e\u9055\u3044\u3068\u4f7f\u3044\u5206\u3051\u65b9<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-5\">Time\u30af\u30e9\u30b9\u3068TimeWithZone\u306e\u7279\u5fb4\u3068\u6d3b\u7528\u30b7\u30fc\u30f3<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-9\">\u5b9f\u8df5\u7684\u306a\u65e5\u4ed8\u64cd\u4f5c\u30c6\u30af\u30cb\u30c3\u30af<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-10\">\u65e5\u4ed8\u306e\u751f\u6210\u3068\u5909\u63db\u306e\u6b63\u3057\u3044\u65b9\u6cd5<\/a>      <\/li>      <li>        <a href=\"#i-11\">\u65e5\u4ed8\u306e\u6bd4\u8f03\u3068\u8a08\u7b97\u3067\u4f7f\u3048\u308b\u4fbf\u5229\u30e1\u30bd\u30c3\u30c9<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-12\">\u30d5\u30a9\u30fc\u30de\u30c3\u30c8\u5909\u63db\u3068\u30d1\u30fc\u30b9\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-13\">\u73fe\u5834\u3067\u906d\u9047\u3059\u308b\u65e5\u4ed8\u51e6\u7406\u306e\u8ab2\u984c\u3068\u89e3\u6c7a\u7b56<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-14\">\u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u95a2\u9023\u306e\u30c8\u30e9\u30d6\u30eb\u3092\u9632\u3050\u5b9f\u88c5\u65b9\u6cd5<\/a>      <\/li>      <li>        <a href=\"#i-15\">\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3092\u8003\u616e\u3057\u305f\u65e5\u4ed8\u51e6\u7406\u306e\u6700\u9069\u5316<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-16\">\u30ec\u30ac\u30b7\u30fc\u30b7\u30b9\u30c6\u30e0\u3067\u306e\u65e5\u4ed8\u30c7\u30fc\u30bf\u79fb\u884c\u306e\u30b3\u30c4<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-17\">\u30c6\u30b9\u30c8\u3068\u30c7\u30d0\u30c3\u30b0\u306e\u30c6\u30af\u30cb\u30c3\u30af<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-18\">\u65e5\u4ed8\u51e6\u7406\u306e\u30e6\u30cb\u30c3\u30c8\u30c6\u30b9\u30c8\u4f5c\u6210\u65b9\u6cd5<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-19\">\u3088\u304f\u3042\u308b\u65e5\u4ed8\u95a2\u9023\u30d0\u30b0\u3068\u305d\u306e\u5bfe\u51e6\u6cd5<\/a>      <\/li>    <\/ul>  <\/li>  <li class=\"last\">    <a href=\"#i-23\">\u5b9f\u8df5\u7684\u306a\u30b3\u30fc\u30c9\u4f8b\u3068\u5fdc\u7528\u30d1\u30bf\u30fc\u30f3<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-24\">Rails\u30d7\u30ed\u30b8\u30a7\u30af\u30c8\u3067\u306e\u5b9f\u88c5\u4f8b\u3068Tips<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-25\">\u5927\u898f\u6a21\u30b7\u30b9\u30c6\u30e0\u3067\u306e\u65e5\u4ed8\u51e6\u7406\u30a2\u30fc\u30ad\u30c6\u30af\u30c1\u30e3<\/a>      <\/li>    <\/ul>  <\/li><\/ul>\n      <a href=\"#\" class=\"sgb-toc-button js-toc-button\" rel=\"nofollow\" data-open-dialog=\"true\"><i class=\"fa fa-list\"><\/i><span class=\"sgb-toc-button__text\">\u76ee\u6b21\u3078<\/span><\/a>\n    <\/div><\/div><h2 class=\"wp-block-heading\" id=\"i-0\">Ruby\u3067\u306e\u65e5\u4ed8\u51e6\u7406\u306e\u57fa\u790e\u77e5\u8b58<\/h2>\n\n\n\n<p>Ruby\u306b\u306f\u65e5\u4ed8\u51e6\u7406\u306e\u305f\u3081\u306e\u8907\u6570\u306e\u30af\u30e9\u30b9\u304c\u7528\u610f\u3055\u308c\u3066\u3044\u307e\u3059\u3002\u9069\u5207\u306a\u30af\u30e9\u30b9\u3092\u9078\u629e\u3059\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u52b9\u7387\u7684\u3067\u4fdd\u5b88\u6027\u306e\u9ad8\u3044\u30b3\u30fc\u30c9\u3092\u66f8\u304f\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-1\">Date\u3068DateTime\u30af\u30e9\u30b9\u306e\u9055\u3044\u3068\u4f7f\u3044\u5206\u3051\u65b9<\/h3>\n\n\n\n<p>Date\u30af\u30e9\u30b9\u3068DateTime\u30af\u30e9\u30b9\u306f\u3001\u305d\u308c\u305e\u308c\u7570\u306a\u308b\u7528\u9014\u306b\u7279\u5316\u3057\u3066\u304a\u308a\u3001\u9069\u5207\u306a\u4f7f\u3044\u5206\u3051\u304c\u91cd\u8981\u3067\u3059\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-2\">Date\u30af\u30e9\u30b9\u306e\u7279\u5fb4\u3068\u4f7f\u7528\u5834\u9762<\/h4>\n\n\n\n<p>Date\u30af\u30e9\u30b9\u306f\u65e5\u4ed8\u306e\u307f\u3092\u6271\u3046\u30b7\u30f3\u30d7\u30eb\u306a\u30af\u30e9\u30b9\u3067\u3059\u3002\u6642\u523b\u60c5\u5831\u304c\u4e0d\u8981\u306a\u5834\u5408\u306b\u6700\u9069\u3067\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">require 'date'\n\n# \u4eca\u65e5\u306e\u65e5\u4ed8\u3092\u53d6\u5f97\ntoday = Date.today\nputs today  #=&gt; 2024-12-03\n\n# \u7279\u5b9a\u306e\u65e5\u4ed8\u3092\u751f\u6210\nbirthday = Date.new(1990, 1, 1)\nputs birthday  #=&gt; 1990-01-01\n\n# \u65e5\u4ed8\u306e\u52a0\u7b97\u30fb\u6e1b\u7b97\nnext_week = today + 7\nlast_week = today - 7\n\n# \u65e5\u4ed8\u306e\u30d5\u30a9\u30fc\u30de\u30c3\u30c8\nputs today.strftime('%Y\u5e74%m\u6708%d\u65e5')  #=&gt; 2024\u5e7412\u670803\u65e5\n\n# \u65e5\u4ed8\u306e\u6bd4\u8f03\nputs birthday &lt; today  #=&gt; true<\/pre>\n\n\n\n<p><strong>\u4f7f\u7528\u5834\u9762\u306e\u4f8b\uff1a<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u751f\u5e74\u6708\u65e5\u306e\u7ba1\u7406<\/li>\n\n\n\n<li>\u30a4\u30d9\u30f3\u30c8\u306e\u958b\u50ac\u65e5\u7a0b\u7ba1\u7406<\/li>\n\n\n\n<li>\u5b9a\u671f\u7684\u306a\u30b9\u30b1\u30b8\u30e5\u30fc\u30eb\u51e6\u7406<\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-3\">DateTime\u30af\u30e9\u30b9\u306e\u7279\u5fb4\u3068\u6d3b\u7528\u65b9\u6cd5<\/h4>\n\n\n\n<p>DateTime\u30af\u30e9\u30b9\u306f\u65e5\u4ed8\u306b\u52a0\u3048\u3066\u6642\u523b\u3082\u6271\u3048\u308b\u9ad8\u6a5f\u80fd\u306a\u30af\u30e9\u30b9\u3067\u3059\u3002\u7cbe\u5bc6\u306a\u6642\u523b\u7ba1\u7406\u304c\u5fc5\u8981\u306a\u5834\u5408\u306b\u4f7f\u7528\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">require 'date'\n\n# \u73fe\u5728\u306e\u65e5\u6642\u3092\u53d6\u5f97\nnow = DateTime.now\nputs now  #=&gt; 2024-12-03T14:30:00+09:00\n\n# \u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u3092\u6307\u5b9a\u3057\u3066\u65e5\u6642\u3092\u751f\u6210\nmeeting = DateTime.new(2024, 12, 3, 15, 30, 0, '+09:00')\nputs meeting  #=&gt; 2024-12-03T15:30:00+09:00\n\n# \u65e5\u6642\u306e\u6f14\u7b97\ntwo_hours_later = now + Rational(2, 24)  # 2\u6642\u9593\u5f8c\nputs two_hours_later\n\n# ISO 8601\u5f62\u5f0f\u3078\u306e\u5909\u63db\nputs now.iso8601  #=&gt; 2024-12-03T14:30:00+09:00<\/pre>\n\n\n\n<p><strong>\u4f7f\u7528\u5834\u9762\u306e\u4f8b\uff1a<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u30b7\u30b9\u30c6\u30e0\u30ed\u30b0\u306e\u8a18\u9332<\/li>\n\n\n\n<li>\u4e88\u7d04\u30b7\u30b9\u30c6\u30e0\u306e\u6642\u9593\u7ba1\u7406<\/li>\n\n\n\n<li>\u30b0\u30ed\u30fc\u30d0\u30eb\u30b5\u30fc\u30d3\u30b9\u306e\u65e5\u6642\u51e6\u7406<\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-4\">\u4f7f\u3044\u5206\u3051\u306e\u30dd\u30a4\u30f3\u30c8<\/h4>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30c7\u30fc\u30bf\u306e\u6027\u8cea\u306b\u3088\u308b\u9078\u629e<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u65e5\u4ed8\u306e\u307f\u306e\u5834\u5408 \u2192 Date<\/li>\n\n\n\n<li>\u6642\u523b\u3092\u542b\u3080\u5834\u5408 \u2192 DateTime<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u306e\u8003\u616e<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Date\u306fDateTime\u3088\u308a\u8efd\u91cf<\/li>\n\n\n\n<li>\u5fc5\u8981\u4ee5\u4e0a\u306e\u6a5f\u80fd\u3092\u6301\u3064\u30af\u30e9\u30b9\u306f\u907f\u3051\u308b<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u306e\u8981\u4ef6<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u304c\u95a2\u4fc2\u306a\u3044 \u2192 Date<\/li>\n\n\n\n<li>\u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u306e\u8003\u616e\u304c\u5fc5\u8981 \u2192 DateTime<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-5\">Time\u30af\u30e9\u30b9\u3068TimeWithZone\u306e\u7279\u5fb4\u3068\u6d3b\u7528\u30b7\u30fc\u30f3<\/h3>\n\n\n\n<p>Ruby\u6a19\u6e96\u306eTime\u30af\u30e9\u30b9\u3068Rails\u56fa\u6709\u306eTimeWithZone\u3067\u306f\u3001\u4f7f\u7528\u76ee\u7684\u3068\u6a5f\u80fd\u304c\u7570\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-6\">Time\u30af\u30e9\u30b9\u306e\u57fa\u672c<\/h4>\n\n\n\n<p>Time\u30af\u30e9\u30b9\u306f\u30b7\u30b9\u30c6\u30e0\u306e\u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u306b\u4f9d\u5b58\u3059\u308b\u6642\u523b\u3092\u6271\u3044\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># \u73fe\u5728\u6642\u523b\u306e\u53d6\u5f97\nnow = Time.now\nputs now  #=&gt; 2024-12-03 14:30:00 +0900\n\n# UNIX\u30bf\u30a4\u30e0\u30b9\u30bf\u30f3\u30d7\u306e\u53d6\u5f97\nputs now.to_i  #=&gt; 1701579000\n\n# \u6642\u523b\u306e\u64cd\u4f5c\none_hour_later = now + 3600  # 1\u6642\u9593\u5f8c\nputs one_hour_later\n\n# \u6642\u523b\u306e\u6bd4\u8f03\nfuture_time = Time.new(2025, 1, 1)\nputs future_time &gt; now  #=&gt; true<\/pre>\n\n\n\n<p><strong>Time\u30af\u30e9\u30b9\u306e\u4e3b\u306a\u7528\u9014\uff1a<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u30b7\u30f3\u30d7\u30eb\u306a\u6642\u523b\u51e6\u7406<\/li>\n\n\n\n<li>UNIX\u30bf\u30a4\u30e0\u30b9\u30bf\u30f3\u30d7\u306e\u6271\u3044<\/li>\n\n\n\n<li>\u30b7\u30b9\u30c6\u30e0\u30ed\u30b0\u306e\u8a18\u9332<\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-7\">TimeWithZone\u306e\u7279\u5fb4\uff08Rails\u74b0\u5883\uff09<\/h4>\n\n\n\n<p>TimeWithZone\u306fRails\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3067\u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u3092\u9069\u5207\u306b\u6271\u3046\u305f\u3081\u306e\u62e1\u5f35\u30af\u30e9\u30b9\u3067\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># Rails\u74b0\u5883\u3067\u306e\u4f8b\nTime.zone = 'Tokyo'\ncurrent_time = Time.zone.now\n\n# \u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u306e\u5909\u63db\nlondon_time = current_time.in_time_zone('London')\nny_time = current_time.in_time_zone('Eastern Time (US &amp; Canada)')\n\n# \u65e5\u6642\u306e\u751f\u6210\nmeeting_time = Time.zone.local(2024, 12, 3, 15, 30)<\/pre>\n\n\n\n<p><strong>TimeWithZone\u306e\u6d3b\u7528\u30b7\u30fc\u30f3\uff1a<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u30b0\u30ed\u30fc\u30d0\u30eb\u30b5\u30fc\u30d3\u30b9\u306e\u958b\u767a<\/li>\n\n\n\n<li>\u30e6\u30fc\u30b6\u30fc\u3054\u3068\u306e\u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u5bfe\u5fdc<\/li>\n\n\n\n<li>\u6b63\u78ba\u306a\u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u5909\u63db\u304c\u5fc5\u8981\u306a\u51e6\u7406<\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-8\">\u5b9f\u88c5\u6642\u306e\u6ce8\u610f\u70b9<\/h4>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u306e\u4e00\u8cab\u6027<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">   # \u63a8\u5968\u3055\u308c\u308b\u5b9f\u88c5\n   Time.zone.now  # Rails\u74b0\u5883\n   Time.current   # Rails\u74b0\u5883\u3067\u306e\u73fe\u5728\u6642\u523b\u53d6\u5f97\u306e\u63a8\u5968\u65b9\u6cd5\n\n   # \u907f\u3051\u308b\u3079\u304d\u5b9f\u88c5\n   Time.now  # \u30b7\u30b9\u30c6\u30e0\u306e\u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u306b\u4f9d\u5b58<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u3068\u306e\u9023\u643a<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">   # config\/application.rb \u3067\u306e\u8a2d\u5b9a\u4f8b\n   config.time_zone = 'Tokyo'\n   config.active_record.default_timezone = :local<\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li><strong>\u30d5\u30a9\u30fc\u30de\u30c3\u30c8\u51e6\u7406<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">   time = Time.zone.now\n   # Rails\u306ehelper\u3092\u4f7f\u7528\n   time.strftime('%Y\u5e74%m\u6708%d\u65e5 %H:%M:%S')  #=&gt; \"2024\u5e7412\u670803\u65e5 14:30:00\"<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u30af\u30e9\u30b9\u3092\u9069\u5207\u306b\u4f7f\u3044\u5206\u3051\u308b\u3053\u3068\u3067\u3001\u4fdd\u5b88\u6027\u304c\u9ad8\u304f\u3001\u30d0\u30b0\u306e\u5c11\u306a\u3044\u65e5\u4ed8\u51e6\u7406\u3092\u5b9f\u88c5\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-9\">\u5b9f\u8df5\u7684\u306a\u65e5\u4ed8\u64cd\u4f5c\u30c6\u30af\u30cb\u30c3\u30af<\/h2>\n\n\n\n<p>\u65e5\u4ed8\u51e6\u7406\u306f\u591a\u304f\u306e\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3067\u91cd\u8981\u306a\u5f79\u5272\u3092\u679c\u305f\u3057\u3066\u3044\u307e\u3059\u3002\u3053\u3053\u3067\u306f\u3001\u5b9f\u52d9\u3067\u983b\u7e41\u306b\u4f7f\u7528\u3055\u308c\u308b\u65e5\u4ed8\u64cd\u4f5c\u30c6\u30af\u30cb\u30c3\u30af\u3092\u89e3\u8aac\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-10\">\u65e5\u4ed8\u306e\u751f\u6210\u3068\u5909\u63db\u306e\u6b63\u3057\u3044\u65b9\u6cd5<\/h3>\n\n\n\n<p>\u65e5\u4ed8\u30c7\u30fc\u30bf\u306e\u751f\u6210\u3068\u5909\u63db\u306f\u3001\u591a\u304f\u306e\u30d0\u30b0\u306e\u539f\u56e0\u3068\u306a\u308a\u3084\u3059\u3044\u51e6\u7406\u3067\u3059\u3002\u4ee5\u4e0b\u306b\u3001\u5b89\u5168\u3067\u4fe1\u983c\u6027\u306e\u9ad8\u3044\u5b9f\u88c5\u65b9\u6cd5\u3092\u793a\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">require 'date'\nrequire 'time'\n\n# \u6587\u5b57\u5217\u304b\u3089\u65e5\u4ed8\u3092\u751f\u6210\u3059\u308b\u5b89\u5168\u306a\u65b9\u6cd5\nbegin\n  # ISO 8601\u5f62\u5f0f\u306e\u6587\u5b57\u5217\u304b\u3089\u306e\u5909\u63db\n  date_from_iso = Date.iso8601('2024-12-03')\n\n  # parse\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u7528\u3059\u308b\u5834\u5408\uff08\u3088\u308a\u67d4\u8edf\u3060\u304c\u6ce8\u610f\u304c\u5fc5\u8981\uff09\n  date_from_string = Date.parse('2024-12-03')\nrescue Date::Error =&gt; e\n  puts \"Invalid date format: #{e.message}\"\nend\n\n# \u73fe\u5728\u65e5\u6642\u304b\u3089\u306e\u5909\u63db\ntoday = Date.today\ncurrent_time = Time.now\ndate_from_time = current_time.to_date\n\n# \u5e74\u6708\u65e5\u304b\u3089\u76f4\u63a5\u751f\u6210\nspecific_date = Date.new(2024, 12, 3)\n\n# \u65e5\u4ed8\u306e\u59a5\u5f53\u6027\u30c1\u30a7\u30c3\u30af\ndef valid_date?(year, month, day)\n  Date.valid_date?(year, month, day)\nend\n\nputs valid_date?(2024, 2, 29)  #=&gt; true\uff08\u958f\u5e74\uff09\nputs valid_date?(2023, 2, 29)  #=&gt; false<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-11\">\u65e5\u4ed8\u306e\u6bd4\u8f03\u3068\u8a08\u7b97\u3067\u4f7f\u3048\u308b\u4fbf\u5229\u30e1\u30bd\u30c3\u30c9<\/h3>\n\n\n\n<p>\u65e5\u4ed8\u306e\u6bd4\u8f03\u3084\u8a08\u7b97\u306f\u3001\u696d\u52d9\u30ed\u30b8\u30c3\u30af\u306e\u4e2d\u6838\u3068\u306a\u308b\u3053\u3068\u304c\u591a\u3044\u51e6\u7406\u3067\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">require 'date'\n\nstart_date = Date.new(2024, 1, 1)\nend_date = Date.new(2024, 12, 31)\n\n# \u65e5\u4ed8\u306e\u6bd4\u8f03\nputs start_date &lt; end_date  #=&gt; true\nputs start_date === end_date  #=&gt; false\n\n# \u65e5\u4ed8\u7bc4\u56f2\u306e\u4f5c\u6210\u3068\u64cd\u4f5c\ndate_range = start_date..end_date\nputs date_range.include?(Date.new(2024, 6, 1))  #=&gt; true\n\n# \u65e5\u6570\u306e\u8a08\u7b97\ndays_between = (end_date - start_date).to_i  #=&gt; 365\n\n# \u55b6\u696d\u65e5\u306e\u8a08\u7b97\nrequire 'business_time'  # gem\u306e\u30a4\u30f3\u30b9\u30c8\u30fc\u30eb\u304c\u5fc5\u8981\n\nBusinessTime::Config.beginning_of_workday = \"9:00 am\"\nBusinessTime::Config.end_of_workday = \"5:00 pm\"\nBusinessTime::Config.holidays = [Date.new(2024, 1, 1)]  # \u795d\u65e5\u306e\u8a2d\u5b9a\n\n# \u55b6\u696d\u65e5\u6570\u306e\u8a08\u7b97\nbusiness_days = start_date.business_days_until(end_date)\n\n# \u6708\u672b\u65e5\u306e\u53d6\u5f97\ndef last_day_of_month(year, month)\n  Date.new(year, month, -1)\nend\n\n# \u5e74\u9f62\u8a08\u7b97\u306e\u4f8b\ndef calculate_age(birthday, reference_date = Date.today)\n  age = reference_date.year - birthday.year\n  age -= 1 if reference_date &lt; birthday + age.years\n  age\nend<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-12\">\u30d5\u30a9\u30fc\u30de\u30c3\u30c8\u5909\u63db\u3068\u30d1\u30fc\u30b9\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9<\/h3>\n\n\n\n<p>\u65e5\u4ed8\u306e\u30d5\u30a9\u30fc\u30de\u30c3\u30c8\u5909\u63db\u3068\u30d1\u30fc\u30b9\u306f\u3001\u5916\u90e8\u30b7\u30b9\u30c6\u30e0\u3068\u306e\u9023\u643a\u3084\u30e6\u30fc\u30b6\u30fc\u5165\u529b\u306e\u51e6\u7406\u3067\u91cd\u8981\u3067\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">require 'date'\n\n# \u57fa\u672c\u7684\u306a\u30d5\u30a9\u30fc\u30de\u30c3\u30c8\u5909\u63db\ndate = Date.new(2024, 12, 3)\n\n# \u6a19\u6e96\u7684\u306a\u65e5\u4ed8\u30d5\u30a9\u30fc\u30de\u30c3\u30c8\nputs date.strftime('%Y-%m-%d')      #=&gt; \"2024-12-03\"\nputs date.strftime('%Y\u5e74%m\u6708%d\u65e5')  #=&gt; \"2024\u5e7412\u670803\u65e5\"\n\n# \u3088\u304f\u4f7f\u7528\u3055\u308c\u308b\u66f8\u5f0f\u4e00\u89a7\nformats = {\n  iso8601: date.iso8601,                    #=&gt; \"2024-12-03\"\n  japanese: date.strftime('%Y\u5e74%m\u6708%d\u65e5'),  #=&gt; \"2024\u5e7412\u670803\u65e5\"\n  slash: date.strftime('%Y\/%m\/%d'),         #=&gt; \"2024\/12\/03\"\n  weekday: date.strftime('%A'),             #=&gt; \"Tuesday\"\n  short_date: date.strftime('%b %d'),       #=&gt; \"Dec 03\"\n}\n\n# \u6587\u5b57\u5217\u304b\u3089\u306e\u30d1\u30fc\u30b9\ndef safe_parse_date(date_string, format = nil)\n  if format\n    Date.strptime(date_string, format)\n  else\n    Date.parse(date_string)\n  end\nrescue Date::Error =&gt; e\n  puts \"\u30d1\u30fc\u30b9\u30a8\u30e9\u30fc: #{e.message}\"\n  nil\nend\n\n# \u4f7f\u7528\u4f8b\ndates = [\n  '2024-12-03',\n  '2024\/12\/03',\n  '20241203',\n  '2024\u5e7412\u67083\u65e5'\n]\n\ndates.each do |date_string|\n  parsed_date = safe_parse_date(date_string)\n  puts \"#{date_string} =&gt; #{parsed_date}\"\nend\n\n# \u30d5\u30a9\u30fc\u30de\u30c3\u30c8\u6307\u5b9a\u4ed8\u304d\u306e\u30d1\u30fc\u30b9\nspecific_format = safe_parse_date('20241203', '%Y%m%d')\n\n# \u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u7528\u306e\u30d5\u30a9\u30fc\u30de\u30c3\u30c8\ndatabase_format = date.to_s  #=&gt; \"2024-12-03\"\n\n# \u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u3092\u8003\u616e\u3057\u305f\u30d5\u30a9\u30fc\u30de\u30c3\u30c8\uff08Rails\u74b0\u5883\uff09\ndef format_with_timezone(datetime, zone = 'Tokyo')\n  datetime.in_time_zone(zone).strftime('%Y-%m-%d %H:%M:%S %Z')\nend<\/pre>\n\n\n\n<p>\u5b9f\u88c5\u306e\u30dd\u30a4\u30f3\u30c8\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30a8\u30e9\u30fc\u30cf\u30f3\u30c9\u30ea\u30f3\u30b0<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u65e5\u4ed8\u30d1\u30fc\u30b9\u306f\u5fc5\u305a\u4f8b\u5916\u51e6\u7406\u3092\u542b\u3081\u308b<\/li>\n\n\n\n<li>\u7121\u52b9\u306a\u65e5\u4ed8\u5165\u529b\u306b\u5bfe\u3059\u308b\u9069\u5207\u306a\u30d5\u30a9\u30fc\u30eb\u30d0\u30c3\u30af\u51e6\u7406\u3092\u7528\u610f<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u306e\u8003\u616e<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5927\u91cf\u306e\u30c7\u30fc\u30bf\u3092\u6271\u3046\u5834\u5408\u306f\u30ad\u30e3\u30c3\u30b7\u30e5\u3092\u691c\u8a0e<\/li>\n\n\n\n<li>\u4e0d\u5fc5\u8981\u306a\u5909\u63db\u306f\u907f\u3051\u308b<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u56fd\u969b\u5316\u5bfe\u5fdc<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u30ed\u30b1\u30fc\u30eb\u306b\u5fdc\u3058\u305f\u30d5\u30a9\u30fc\u30de\u30c3\u30c8<\/li>\n\n\n\n<li>\u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u306e\u9069\u5207\u306a\u51e6\u7406<\/li>\n<\/ul>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u30c6\u30af\u30cb\u30c3\u30af\u3092\u9069\u5207\u306b\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3067\u3001\u5805\u7262\u306a\u65e5\u4ed8\u51e6\u7406\u3092\u5b9f\u88c5\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-13\">\u73fe\u5834\u3067\u906d\u9047\u3059\u308b\u65e5\u4ed8\u51e6\u7406\u306e\u8ab2\u984c\u3068\u89e3\u6c7a\u7b56<\/h2>\n\n\n\n<p>\u5b9f\u969b\u306e\u958b\u767a\u73fe\u5834\u3067\u306f\u3001\u65e5\u4ed8\u51e6\u7406\u306b\u95a2\u3059\u308b\u69d8\u3005\u306a\u8ab2\u984c\u306b\u76f4\u9762\u3057\u307e\u3059\u3002\u3053\u3053\u3067\u306f\u3001\u3088\u304f\u3042\u308b\u554f\u984c\u3068\u305d\u306e\u5177\u4f53\u7684\u306a\u89e3\u6c7a\u7b56\u3092\u89e3\u8aac\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-14\">\u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u95a2\u9023\u306e\u30c8\u30e9\u30d6\u30eb\u3092\u9632\u3050\u5b9f\u88c5\u65b9\u6cd5<\/h3>\n\n\n\n<p>\u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u306e\u6271\u3044\u306f\u3001\u30b0\u30ed\u30fc\u30d0\u30eb\u30b5\u30fc\u30d3\u30b9\u3092\u958b\u767a\u3059\u308b\u969b\u306e\u5927\u304d\u306a\u8ab2\u984c\u3068\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># Rails\u74b0\u5883\u3067\u306e\u63a8\u5968\u5b9f\u88c5\nclass Application &lt; Rails::Application\n  config.time_zone = 'Tokyo'\n  config.active_record.default_timezone = :utc\nend\n\nclass User &lt; ApplicationRecord\n  # \u30e6\u30fc\u30b6\u30fc\u3054\u3068\u306e\u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u8a2d\u5b9a\n  validates :time_zone, inclusion: { in: ActiveSupport::TimeZone.all.map(&amp;:name) }\nend\n\nclass ApplicationController &lt; ActionController::Base\n  around_action :set_time_zone, if: :current_user\n\n  private\n\n  def set_time_zone(&amp;block)\n    Time.use_zone(current_user.time_zone, &amp;block)\n  end\nend\n\n# \u65e5\u6642\u30c7\u30fc\u30bf\u306e\u4fdd\u5b58\u3068\u8868\u793a\nclass Event &lt; ApplicationRecord\n  def start_time_in_user_zone(user)\n    start_time.in_time_zone(user.time_zone)\n  end\n\n  # \u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u3092\u610f\u8b58\u3057\u305f\u65e5\u4ed8\u6bd4\u8f03\n  scope :upcoming, -&gt; {\n    where('start_time &gt; ?', Time.current)\n  }\nend<\/pre>\n\n\n\n<p>\u5b9f\u88c5\u306e\u30dd\u30a4\u30f3\u30c8\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306fUTC\u3067\u4fdd\u5b58<\/li>\n\n\n\n<li>\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u5c64\u3067\u9069\u5207\u306a\u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u5909\u63db<\/li>\n\n\n\n<li>\u30e6\u30fc\u30b6\u30fc\u5165\u529b\u6642\u306e\u9069\u5207\u306a\u5909\u63db\u51e6\u7406<\/li>\n<\/ol>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-15\">\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3092\u8003\u616e\u3057\u305f\u65e5\u4ed8\u51e6\u7406\u306e\u6700\u9069\u5316<\/h3>\n\n\n\n<p>\u65e5\u4ed8\u51e6\u7406\u306f\u3001\u7279\u306b\u5927\u91cf\u306e\u30ec\u30b3\u30fc\u30c9\u3092\u6271\u3046\u5834\u5408\u306b\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u4e0a\u306e\u8ab2\u984c\u3068\u306a\u308b\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">class DateProcessor\n  # \u30e1\u30e2\u5316\u3092\u4f7f\u7528\u3057\u305f\u6700\u9069\u5316\n  def self.calculate_fiscal_year(date)\n    @fiscal_years ||= {}\n    @fiscal_years[date.to_s] ||= begin\n      if date.month &gt;= 4\n        date.year\n      else\n        date.year - 1\n      end\n    end\n  end\n\n  # \u30d0\u30c3\u30c1\u51e6\u7406\u3067\u306e\u6700\u9069\u5316\u4f8b\n  def self.process_date_range(start_date, end_date, batch_size = 1000)\n    current_date = start_date\n    while current_date &lt;= end_date\n      dates = (current_date...[current_date + batch_size.days, end_date + 1.day].min).to_a\n\n      # \u30d0\u30c3\u30c1\u51e6\u7406\u306e\u5b9f\u884c\n      ActiveRecord::Base.transaction do\n        dates.each do |date|\n          yield(date) if block_given?\n        end\n      end\n\n      current_date += batch_size.days\n    end\n  end\n\n  # \u30a4\u30f3\u30c7\u30c3\u30af\u30b9\u3092\u6d3b\u7528\u3057\u305f\u30af\u30a8\u30ea\u6700\u9069\u5316\n  scope :by_date_range, -&gt;(start_date, end_date) {\n    where(created_at: start_date.beginning_of_day..end_date.end_of_day)\n      .includes(:related_records)\n      .index_by(&amp;:date)\n  }\nend\n\n# \u30ad\u30e3\u30c3\u30b7\u30e5\u3092\u6d3b\u7528\u3057\u305f\u65e5\u4ed8\u8a08\u7b97\nclass HolidayCalculator\n  def self.business_days_between(start_date, end_date)\n    Rails.cache.fetch([\"business_days\", start_date, end_date]) do\n      calculate_business_days(start_date, end_date)\n    end\n  end\n\n  private\n\n  def self.calculate_business_days(start_date, end_date)\n    # \u5b9f\u969b\u306e\u8a08\u7b97\u30ed\u30b8\u30c3\u30af\n  end\nend<\/pre>\n\n\n\n<p>\u6700\u9069\u5316\u306e\u30dd\u30a4\u30f3\u30c8\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u9069\u5207\u306a\u30a4\u30f3\u30c7\u30c3\u30af\u30b9\u8a2d\u8a08<\/li>\n\n\n\n<li>\u30d0\u30c3\u30c1\u51e6\u7406\u306e\u6d3b\u7528<\/li>\n\n\n\n<li>\u30ad\u30e3\u30c3\u30b7\u30e5\u6226\u7565\u306e\u5b9f\u88c5<\/li>\n\n\n\n<li>\u4e0d\u8981\u306a\u65e5\u4ed8\u5909\u63db\u306e\u524a\u6e1b<\/li>\n<\/ol>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-16\">\u30ec\u30ac\u30b7\u30fc\u30b7\u30b9\u30c6\u30e0\u3067\u306e\u65e5\u4ed8\u30c7\u30fc\u30bf\u79fb\u884c\u306e\u30b3\u30c4<\/h3>\n\n\n\n<p>\u30ec\u30ac\u30b7\u30fc\u30b7\u30b9\u30c6\u30e0\u306e\u79fb\u884c\u6642\u306b\u306f\u3001\u69d8\u3005\u306a\u65e5\u4ed8\u30d5\u30a9\u30fc\u30de\u30c3\u30c8\u3084\u7279\u6b8a\u306a\u51e6\u7406\u30eb\u30fc\u30eb\u306b\u5bfe\u5fdc\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">class DateMigrator\n  class &lt;&lt; self\n    def migrate_legacy_dates(records)\n      records.find_each do |record|\n        normalized_date = normalize_legacy_date(record.original_date)\n        record.update!(new_date: normalized_date)\n      rescue StandardError =&gt; e\n        log_migration_error(record, e)\n      end\n    end\n\n    private\n\n    def normalize_legacy_date(date_string)\n      # \u69d8\u3005\u306a\u5f62\u5f0f\u306b\u5bfe\u5fdc\n      formats = [\n        '%Y\/%m\/%d',\n        '%Y-%m-%d',\n        '%Y.%m.%d',\n        '%Y\u5e74%m\u6708%d\u65e5'\n      ]\n\n      formats.each do |format|\n        begin\n          return Date.strptime(date_string, format)\n        rescue Date::Error\n          next\n        end\n      end\n\n      raise \"Unknown date format: #{date_string}\"\n    end\n\n    def log_migration_error(record, error)\n      Rails.logger.error(\n        \"Date migration failed for record #{record.id}: #{error.message}\"\n      )\n    end\n  end\nend\n\n# \u79fb\u884c\u30b9\u30af\u30ea\u30d7\u30c8\u306e\u4f8b\nclass LegacyDateMigrationTask\n  def self.execute\n    # \u9032\u6357\u7ba1\u7406\u7528\u306e\u30ab\u30a6\u30f3\u30bf\u30fc\n    total = LegacyRecord.count\n    processed = 0\n\n    LegacyRecord.find_each do |record|\n      begin\n        # \u30c7\u30fc\u30bf\u306e\u6b63\u898f\u5316\u3068\u5909\u63db\n        normalized_date = DateMigrator.normalize_legacy_date(record.date_field)\n\n        # \u65b0\u30b7\u30b9\u30c6\u30e0\u3067\u306e\u4fdd\u5b58\n        NewRecord.create!(\n          date: normalized_date,\n          additional_data: record.other_fields\n        )\n\n        processed += 1\n        puts \"Processed #{processed}\/#{total} records\" if (processed % 100).zero?\n      rescue =&gt; e\n        # \u30a8\u30e9\u30fc\u30ed\u30b0\u306e\u8a18\u9332\n        Rails.logger.error(\"Migration failed for record #{record.id}: #{e.message}\")\n      end\n    end\n  end\nend<\/pre>\n\n\n\n<p>\u79fb\u884c\u6642\u306e\u30dd\u30a4\u30f3\u30c8\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30c7\u30fc\u30bf\u306e\u691c\u8a3c\u3068\u6b63\u898f\u5316<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5165\u529b\u30c7\u30fc\u30bf\u306e\u59a5\u5f53\u6027\u30c1\u30a7\u30c3\u30af<\/li>\n\n\n\n<li>\u30d5\u30a9\u30fc\u30de\u30c3\u30c8\u306e\u7d71\u4e00\u5316<\/li>\n\n\n\n<li>\u7570\u5e38\u5024\u306e\u691c\u51fa\u3068\u5bfe\u5fdc<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30a8\u30e9\u30fc\u30cf\u30f3\u30c9\u30ea\u30f3\u30b0<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u9069\u5207\u306a\u30ed\u30b0\u8a18\u9332<\/li>\n\n\n\n<li>\u5931\u6557\u3057\u305f\u30ec\u30b3\u30fc\u30c9\u306e\u518d\u51e6\u7406\u65b9\u6cd5<\/li>\n\n\n\n<li>\u30d0\u30c3\u30af\u30a2\u30c3\u30d7\u3068\u5fa9\u5143\u624b\u9806<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u8003\u616e<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u30d0\u30c3\u30c1\u30b5\u30a4\u30ba\u306e\u9069\u5207\u306a\u8a2d\u5b9a<\/li>\n\n\n\n<li>\u30a4\u30f3\u30c7\u30c3\u30af\u30b9\u306e\u6d3b\u7528<\/li>\n\n\n\n<li>\u51e6\u7406\u306e\u5206\u6563\u5316<\/li>\n<\/ul>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u89e3\u6c7a\u7b56\u3092\u9069\u5207\u306b\u5b9f\u88c5\u3059\u308b\u3053\u3068\u3067\u3001\u591a\u304f\u306e\u65e5\u4ed8\u51e6\u7406\u306e\u8ab2\u984c\u306b\u52b9\u679c\u7684\u306b\u5bfe\u5fdc\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-17\">\u30c6\u30b9\u30c8\u3068\u30c7\u30d0\u30c3\u30b0\u306e\u30c6\u30af\u30cb\u30c3\u30af<\/h2>\n\n\n\n<p>\u65e5\u4ed8\u51e6\u7406\u306e\u30c6\u30b9\u30c8\u3068\u30c7\u30d0\u30c3\u30b0\u306f\u3001\u30a8\u30c3\u30b8\u30b1\u30fc\u30b9\u3084\u74b0\u5883\u4f9d\u5b58\u306e\u554f\u984c\u304c\u591a\u3044\u305f\u3081\u3001\u7279\u306b\u6ce8\u610f\u304c\u5fc5\u8981\u3067\u3059\u3002\u3053\u3053\u3067\u306f\u52b9\u679c\u7684\u306a\u30c6\u30b9\u30c8\u65b9\u6cd5\u3068\u30c7\u30d0\u30c3\u30b0\u624b\u6cd5\u3092\u89e3\u8aac\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-18\">\u65e5\u4ed8\u51e6\u7406\u306e\u30e6\u30cb\u30c3\u30c8\u30c6\u30b9\u30c8\u4f5c\u6210\u65b9\u6cd5<\/h3>\n\n\n\n<p>RSpec\u3092\u4f7f\u7528\u3057\u305f\u65e5\u4ed8\u51e6\u7406\u306e\u30c6\u30b9\u30c8\u4f8b\u3092\u793a\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">require 'rails_helper'\n\nRSpec.describe DateProcessor do\n  # \u6642\u9593\u3092\u56fa\u5b9a\u3057\u3066\u30c6\u30b9\u30c8\u3092\u5b9f\u884c\n  before do\n    Timecop.freeze(Time.zone.local(2024, 12, 3))\n  end\n\n  after do\n    Timecop.return\n  end\n\n  describe '#calculate_date_range' do\n    let(:processor) { DateProcessor.new }\n\n    context '\u901a\u5e38\u306e\u65e5\u4ed8\u7bc4\u56f2\u306e\u5834\u5408' do\n      it '\u6b63\u3057\u3044\u65e5\u6570\u3092\u8fd4\u3059\u3053\u3068' do\n        start_date = Date.new(2024, 1, 1)\n        end_date = Date.new(2024, 12, 31)\n\n        result = processor.calculate_date_range(start_date, end_date)\n        expect(result).to eq 366 # 2024\u5e74\u306f\u958f\u5e74\n      end\n    end\n\n    context '\u7121\u52b9\u306a\u65e5\u4ed8\u7bc4\u56f2\u306e\u5834\u5408' do\n      it '\u30a8\u30e9\u30fc\u3092\u767a\u751f\u3055\u305b\u308b\u3053\u3068' do\n        start_date = Date.new(2024, 12, 31)\n        end_date = Date.new(2024, 1, 1)\n\n        expect {\n          processor.calculate_date_range(start_date, end_date)\n        }.to raise_error(InvalidDateRangeError)\n      end\n    end\n  end\n\n  describe '#parse_date' do\n    context '\u6709\u52b9\u306a\u65e5\u4ed8\u6587\u5b57\u5217\u306e\u5834\u5408' do\n      valid_formats = {\n        'ISO\u5f62\u5f0f' =&gt; ['2024-12-03', Date.new(2024, 12, 3)],\n        '\u65e5\u672c\u8a9e\u5f62\u5f0f' =&gt; ['2024\u5e7412\u67083\u65e5', Date.new(2024, 12, 3)],\n        '\u30b9\u30e9\u30c3\u30b7\u30e5\u5f62\u5f0f' =&gt; ['2024\/12\/03', Date.new(2024, 12, 3)]\n      }\n\n      valid_formats.each do |format_name, (input, expected)|\n        it \"#{format_name}\u3092\u6b63\u3057\u304f\u30d1\u30fc\u30b9\u3067\u304d\u308b\u3053\u3068\" do\n          expect(processor.parse_date(input)).to eq expected\n        end\n      end\n    end\n\n    context '\u7121\u52b9\u306a\u65e5\u4ed8\u6587\u5b57\u5217\u306e\u5834\u5408' do\n      invalid_formats = [\n        '2024-13-01',  # \u7121\u52b9\u306a\u6708\n        '2024-04-31',  # \u5b58\u5728\u3057\u306a\u3044\u65e5\n        'invalid date' # \u4e0d\u6b63\u306a\u5f62\u5f0f\n      ]\n\n      invalid_formats.each do |invalid_input|\n        it \"#{invalid_input}\u3067\u30a8\u30e9\u30fc\u3092\u767a\u751f\u3055\u305b\u308b\u3053\u3068\" do\n          expect {\n            processor.parse_date(invalid_input)\n          }.to raise_error(DateParseError)\n        end\n      end\n    end\n  end\n\n  # \u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u306e\u30c6\u30b9\u30c8\n  describe '#convert_timezone' do\n    let(:datetime) { Time.zone.local(2024, 12, 3, 12, 0, 0) }\n\n    it '\u7570\u306a\u308b\u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u9593\u3067\u6b63\u3057\u304f\u5909\u63db\u3067\u304d\u308b\u3053\u3068' do\n      result = processor.convert_timezone(datetime, 'Asia\/Tokyo', 'UTC')\n      expect(result.hour).to eq 3 # UTC = JST - 9\u6642\u9593\n    end\n  end\nend<\/pre>\n\n\n\n<p>\u30c6\u30b9\u30c8\u4f5c\u6210\u306e\u30dd\u30a4\u30f3\u30c8\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30c6\u30b9\u30c8\u30c7\u30fc\u30bf\u306e\u6e96\u5099<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5883\u754c\u5024\u306e\u30c6\u30b9\u30c8<\/li>\n\n\n\n<li>\u30a8\u30c3\u30b8\u30b1\u30fc\u30b9\u306e\u8003\u616e<\/li>\n\n\n\n<li>\u69d8\u3005\u306a\u65e5\u4ed8\u30d5\u30a9\u30fc\u30de\u30c3\u30c8\u306e\u30c6\u30b9\u30c8<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30e2\u30c3\u30af\u3068\u30b9\u30bf\u30d6\u306e\u6d3b\u7528<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">   # \u73fe\u5728\u6642\u523b\u3092\u30e2\u30c3\u30af\u5316\u3059\u308b\u4f8b\n   allow(Time).to receive(:current).and_return(\n     Time.zone.local(2024, 12, 3)\n   )<\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li><strong>\u30c6\u30b9\u30c8\u306e\u81ea\u52d5\u5316<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">   # CircleCI\u306e\u8a2d\u5b9a\u4f8b\n   # .circleci\/config.yml\n   version: 2.1\n   jobs:\n     test:\n       docker:\n         - image: circleci\/ruby:3.2.0\n       steps:\n         - checkout\n         - run: bundle install\n         - run: bundle exec rspec<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-19\">\u3088\u304f\u3042\u308b\u65e5\u4ed8\u95a2\u9023\u30d0\u30b0\u3068\u305d\u306e\u5bfe\u51e6\u6cd5<\/h3>\n\n\n\n<p>\u65e5\u4ed8\u51e6\u7406\u3067\u767a\u751f\u3057\u3084\u3059\u3044\u30d0\u30b0\u3068\u305d\u306e\u5bfe\u51e6\u65b9\u6cd5\u3092\u89e3\u8aac\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-20\">1. \u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u95a2\u9023\u306e\u30d0\u30b0<\/h4>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># \u554f\u984c\u306e\u3042\u308b\u30b3\u30fc\u30c9\ndef schedule_event(start_time)\n  Event.create!(\n    start_time: Time.parse(start_time)  # \u30b7\u30b9\u30c6\u30e0\u306e\u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u306b\u4f9d\u5b58\n  )\nend\n\n# \u4fee\u6b63\u5f8c\u306e\u30b3\u30fc\u30c9\ndef schedule_event(start_time)\n  Event.create!(\n    start_time: Time.zone.parse(start_time)  # \u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u306e\u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u3092\u4f7f\u7528\n  )\nend\n\n# \u30c7\u30d0\u30c3\u30b0\u7528\u306e\u30d8\u30eb\u30d1\u30fc\u30e1\u30bd\u30c3\u30c9\ndef debug_timezone_info(datetime)\n  {\n    original: datetime,\n    timezone: datetime.zone,\n    utc_offset: datetime.utc_offset,\n    utc_time: datetime.utc\n  }\nend<\/pre>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-21\">2. \u65e5\u4ed8\u8a08\u7b97\u306e\u30d0\u30b0<\/h4>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># \u554f\u984c\u306e\u3042\u308b\u30b3\u30fc\u30c9\ndef next_month(date)\n  date + 1.month  # \u6708\u672b\u65e5\u3067\u306e\u8a08\u7b97\u304c\u4e0d\u9069\u5207\nend\n\n# \u4fee\u6b63\u5f8c\u306e\u30b3\u30fc\u30c9\ndef next_month(date)\n  date.next_month.change(day: [date.day, date.next_month.end_of_month.day].min)\nend\n\n# \u30c7\u30d0\u30c3\u30b0\u7528\u306e\u30c6\u30b9\u30c8\u30b1\u30fc\u30b9\ndef test_edge_cases\n  edge_dates = [\n    Date.new(2024, 1, 31),  # 31\u65e5\u3042\u308b\u6708\n    Date.new(2024, 2, 29),  # \u958f\u5e74\n    Date.new(2023, 2, 28)   # \u975e\u958f\u5e74\n  ]\n\n  edge_dates.each do |date|\n    puts \"Original: #{date}\"\n    puts \"Next month: #{next_month(date)}\"\n  end\nend<\/pre>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-22\">3. \u30d1\u30fc\u30b9\u30a8\u30e9\u30fc\u306e\u5bfe\u51e6<\/h4>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># \u30c7\u30d0\u30c3\u30b0\u7528\u306e\u30ed\u30ac\u30fc\u8a2d\u5b9a\nclass DateDebugLogger\n  def self.log_parse_attempt(string, format = nil)\n    Rails.logger.debug(\n      \"Date parse attempt: \" \\\n      \"Input: #{string}, \" \\\n      \"Format: #{format || 'auto'}\"\n    )\n\n    begin\n      result = format ? Date.strptime(string, format) : Date.parse(string)\n      Rails.logger.debug(\"Parse success: #{result}\")\n      result\n    rescue Date::Error =&gt; e\n      Rails.logger.error(\"Parse failed: #{e.message}\")\n      raise\n    end\n  end\nend\n\n# \u4f7f\u7528\u4f8b\ndef safe_parse_with_logging(date_string)\n  DateDebugLogger.log_parse_attempt(date_string)\nrescue Date::Error =&gt; e\n  # \u30a8\u30e9\u30fc\u30cf\u30f3\u30c9\u30ea\u30f3\u30b0\n  nil\nend<\/pre>\n\n\n\n<p>\u30c7\u30d0\u30c3\u30b0\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30ed\u30b0\u306e\u6d3b\u7528<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">   # config\/environments\/development.rb\n   config.logger = Logger.new(STDOUT)\n   config.log_level = :debug<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u30c7\u30d0\u30c3\u30b0\u7528\u30d8\u30eb\u30d1\u30fc\u30e1\u30bd\u30c3\u30c9<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">   module DateDebugHelper\n     def self.inspect_date(date)\n       {\n         class: date.class,\n         value: date,\n         utc: date.respond_to?(:utc?) ? date.utc? : nil,\n         zone: date.respond_to?(:zone) ? date.zone : nil,\n         methods: date.methods - Object.methods\n       }\n     end\n   end<\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li><strong>\u30c6\u30b9\u30c8\u74b0\u5883\u306e\u6574\u5099<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">   # spec\/support\/time_helpers.rb\n   RSpec.configure do |config|\n     config.include ActiveSupport::Testing::TimeHelpers\n   end<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u30c6\u30b9\u30c8\u3068\u30c7\u30d0\u30c3\u30b0\u624b\u6cd5\u3092\u9069\u5207\u306b\u6d3b\u7528\u3059\u308b\u3053\u3068\u3067\u3001\u65e5\u4ed8\u51e6\u7406\u306e\u54c1\u8cea\u3092\u9ad8\u3081\u3001\u30d0\u30b0\u306e\u65e9\u671f\u767a\u898b\u3068\u4fee\u6b63\u304c\u53ef\u80fd\u3068\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-23\">\u5b9f\u8df5\u7684\u306a\u30b3\u30fc\u30c9\u4f8b\u3068\u5fdc\u7528\u30d1\u30bf\u30fc\u30f3<\/h2>\n\n\n\n<p>\u5b9f\u969b\u306e\u958b\u767a\u73fe\u5834\u3067\u306e\u65e5\u4ed8\u51e6\u7406\u306e\u5b9f\u88c5\u4f8b\u3068\u3001\u5927\u898f\u6a21\u30b7\u30b9\u30c6\u30e0\u3067\u306e\u8a2d\u8a08\u30d1\u30bf\u30fc\u30f3\u3092\u7d39\u4ecb\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-24\">Rails\u30d7\u30ed\u30b8\u30a7\u30af\u30c8\u3067\u306e\u5b9f\u88c5\u4f8b\u3068Tips<\/h3>\n\n\n\n<p>Rails\u30d7\u30ed\u30b8\u30a7\u30af\u30c8\u3067\u3088\u304f\u906d\u9047\u3059\u308b\u65e5\u4ed8\u51e6\u7406\u306e\u5b9f\u88c5\u4f8b\u3092\u793a\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># app\/models\/concerns\/date_manageable.rb\nmodule DateManageable\n  extend ActiveSupport::Concern\n\n  included do\n    scope :created_today, -&gt; { where(created_at: Time.current.all_day) }\n    scope :created_this_week, -&gt; { where(created_at: Time.current.all_week) }\n    scope :created_this_month, -&gt; { where(created_at: Time.current.all_month) }\n  end\n\n  def formatted_date(attribute, format = :default)\n    return unless self[attribute]\n\n    case format\n    when :default\n      I18n.l(self[attribute], format: :default)\n    when :short\n      I18n.l(self[attribute], format: :short)\n    when :long\n      I18n.l(self[attribute], format: :long)\n    end\n  end\nend\n\n# app\/models\/event.rb\nclass Event &lt; ApplicationRecord\n  include DateManageable\n\n  belongs_to :user\n  validates :start_date, :end_date, presence: true\n  validate :end_date_after_start_date\n\n  # \u65e5\u4ed8\u306e\u91cd\u8907\u30c1\u30a7\u30c3\u30af\n  validate :no_date_overlap\n\n  # \u30a4\u30d9\u30f3\u30c8\u306e\u671f\u9593\u3092\u8a08\u7b97\n  def duration_in_days\n    (end_date - start_date).to_i + 1\n  end\n\n  # \u55b6\u696d\u65e5\u6570\u3092\u8a08\u7b97\n  def business_days\n    (start_date..end_date).count { |date| \n      date.on_weekday? &amp;&amp; !Holiday.exists?(date: date)\n    }\n  end\n\n  # \u30a4\u30d9\u30f3\u30c8\u304c\u73fe\u5728\u9032\u884c\u4e2d\u304b\u3069\u3046\u304b\n  def ongoing?\n    start_date &lt;= Date.current &amp;&amp; end_date &gt;= Date.current\n  end\n\n  private\n\n  def end_date_after_start_date\n    return if end_date.blank? || start_date.blank?\n\n    if end_date &lt; start_date\n      errors.add(:end_date, \"must be after the start date\")\n    end\n  end\n\n  def no_date_overlap\n    overlapping_event = Event.where(user_id: user_id)\n                            .where.not(id: id)\n                            .where('start_date &lt;= ? AND end_date &gt;= ?', \n                                   end_date, start_date)\n                            .exists?\n\n    if overlapping_event\n      errors.add(:base, \"Event dates overlap with another event\")\n    end\n  end\nend\n\n# app\/models\/holiday.rb\nclass Holiday &lt; ApplicationRecord\n  validates :date, presence: true, uniqueness: true\n\n  # \u795d\u65e5\u30c7\u30fc\u30bf\u306e\u4e00\u62ec\u30a4\u30f3\u30dd\u30fc\u30c8\n  def self.import_from_csv(file)\n    require 'csv'\n\n    ActiveRecord::Base.transaction do\n      CSV.foreach(file.path, headers: true) do |row|\n        Holiday.create!(\n          date: Date.parse(row['date']),\n          name: row['name'],\n          description: row['description']\n        )\n      end\n    end\n  end\nend\n\n# app\/services\/date_range_service.rb\nclass DateRangeService\n  def initialize(start_date, end_date)\n    @start_date = start_date\n    @end_date = end_date\n  end\n\n  def business_days\n    calculate_business_days\n  end\n\n  def total_days\n    (@end_date - @start_date).to_i + 1\n  end\n\n  private\n\n  def calculate_business_days\n    (@start_date..@end_date).count do |date|\n      date.on_weekday? &amp;&amp; !Holiday.exists?(date: date)\n    end\n  end\nend\n\n# app\/controllers\/events_controller.rb\nclass EventsController &lt; ApplicationController\n  def index\n    @events = Event.where(start_date: date_range)\n                   .includes(:user)\n                   .order(start_date: :asc)\n  end\n\n  private\n\n  def date_range\n    start_date = params[:start_date].present? ? \n                 Date.parse(params[:start_date]) : \n                 Date.current.beginning_of_month\n\n    end_date = params[:end_date].present? ? \n               Date.parse(params[:end_date]) : \n               start_date.end_of_month\n\n    start_date..end_date\n  end\nend<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-25\">\u5927\u898f\u6a21\u30b7\u30b9\u30c6\u30e0\u3067\u306e\u65e5\u4ed8\u51e6\u7406\u30a2\u30fc\u30ad\u30c6\u30af\u30c1\u30e3<\/h3>\n\n\n\n<p>\u5927\u898f\u6a21\u30b7\u30b9\u30c6\u30e0\u3067\u306f\u3001\u65e5\u4ed8\u51e6\u7406\u3092\u52b9\u7387\u7684\u306b\u7ba1\u7406\u3059\u308b\u305f\u3081\u306e\u8a2d\u8a08\u30d1\u30bf\u30fc\u30f3\u304c\u91cd\u8981\u3067\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># app\/services\/date_processing\/base_processor.rb\nmodule DateProcessing\n  class BaseProcessor\n    def initialize(config = {})\n      @config = default_config.merge(config)\n    end\n\n    private\n\n    def default_config\n      {\n        timezone: 'UTC',\n        date_format: '%Y-%m-%d',\n        datetime_format: '%Y-%m-%d %H:%M:%S'\n      }\n    end\n  end\nend\n\n# app\/services\/date_processing\/date_converter.rb\nmodule DateProcessing\n  class DateConverter &lt; BaseProcessor\n    def convert(date_string, source_format = nil)\n      return date_string if date_string.is_a?(Date)\n\n      if source_format\n        Date.strptime(date_string, source_format)\n      else\n        Date.parse(date_string)\n      end\n    rescue Date::Error =&gt; e\n      Rails.logger.error(\"Date conversion error: #{e.message}\")\n      raise DateProcessingError, \"Invalid date format: #{date_string}\"\n    end\n  end\nend\n\n# app\/services\/date_processing\/date_range_processor.rb\nmodule DateProcessing\n  class DateRangeProcessor &lt; BaseProcessor\n    def initialize(config = {})\n      super\n      @converter = DateConverter.new(config)\n    end\n\n    def process_range(start_date, end_date)\n      start_date = @converter.convert(start_date)\n      end_date = @converter.convert(end_date)\n\n      validate_range(start_date, end_date)\n      create_date_range(start_date, end_date)\n    end\n\n    private\n\n    def validate_range(start_date, end_date)\n      if end_date &lt; start_date\n        raise DateProcessingError, \"End date must be after start date\"\n      end\n    end\n\n    def create_date_range(start_date, end_date)\n      (start_date..end_date).to_a\n    end\n  end\nend\n\n# config\/initializers\/date_processing.rb\nRails.application.config.to_prepare do\n  DateProcessing.configure do |config|\n    config.default_timezone = 'UTC'\n    config.date_formats = {\n      default: '%Y-%m-%d',\n      japanese: '%Y\u5e74%m\u6708%d\u65e5',\n      slash: '%Y\/%m\/%d'\n    }\n  end\nend\n\n# lib\/date_processing_error.rb\nclass DateProcessingError &lt; StandardError; end\n\n# app\/jobs\/date_processing_job.rb\nclass DateProcessingJob &lt; ApplicationJob\n  queue_as :default\n\n  def perform(start_date, end_date, options = {})\n    processor = DateProcessing::DateRangeProcessor.new(options)\n    dates = processor.process_range(start_date, end_date)\n\n    dates.each do |date|\n      process_single_date(date)\n    end\n  end\n\n  private\n\n  def process_single_date(date)\n    # \u65e5\u4ed8\u3054\u3068\u306e\u51e6\u7406\u3092\u5b9f\u88c5\n  end\nend<\/pre>\n\n\n\n<p>\u5b9f\u88c5\u306e\u30dd\u30a4\u30f3\u30c8\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30e2\u30b8\u30e5\u30fc\u30eb\u5316\u3068\u8cac\u4efb\u306e\u5206\u96e2<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u65e5\u4ed8\u51e6\u7406\u306e\u8cac\u4efb\u3092\u660e\u78ba\u306b\u5206\u96e2<\/li>\n\n\n\n<li>\u518d\u5229\u7528\u53ef\u80fd\u306a\u30b3\u30f3\u30dd\u30fc\u30cd\u30f3\u30c8\u8a2d\u8a08<\/li>\n\n\n\n<li>\u30c6\u30b9\u30bf\u30d3\u30ea\u30c6\u30a3\u306e\u5411\u4e0a<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30a8\u30e9\u30fc\u30cf\u30f3\u30c9\u30ea\u30f3\u30b0<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">   # app\/controllers\/application_controller.rb\n   class ApplicationController &lt; ActionController::Base\n     rescue_from DateProcessingError do |e|\n       render json: { error: e.message }, status: :unprocessable_entity\n     end\n   end<\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li><strong>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u6700\u9069\u5316<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">   # config\/initializers\/cache_store.rb\n   Rails.application.config.cache_store = :redis_cache_store, {\n     url: ENV['REDIS_URL'],\n     expires_in: 1.day\n   }<\/pre>\n\n\n\n<ol start=\"4\" class=\"wp-block-list\">\n<li><strong>\u56fd\u969b\u5316\u5bfe\u5fdc<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">   # config\/locales\/ja.yml\n   ja:\n     date:\n       formats:\n         default: \"%Y\/%m\/%d\"\n         long: \"%Y\u5e74%m\u6708%d\u65e5\"\n         short: \"%m\/%d\"<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u5b9f\u88c5\u4f8b\u3068\u8a2d\u8a08\u30d1\u30bf\u30fc\u30f3\u3092\u53c2\u8003\u306b\u3001\u30d7\u30ed\u30b8\u30a7\u30af\u30c8\u306e\u8981\u4ef6\u306b\u5408\u308f\u305b\u305f\u9069\u5207\u306a\u65e5\u4ed8\u51e6\u7406\u30b7\u30b9\u30c6\u30e0\u3092\u69cb\u7bc9\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Warning: Undefined array key &#8220;is_admin&#8221; in \/home\/xs392991\/dexall.co.jp\/public_html\/articles\/wp-content\/themes\/ &#8230; <\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[],"class_list":{"0":"post-1263","1":"post","2":"type-post","3":"status-publish","4":"format-standard","6":"category-ruby","7":"nothumb"},"_links":{"self":[{"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/posts\/1263","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1263"}],"version-history":[{"count":1,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/posts\/1263\/revisions"}],"predecessor-version":[{"id":1265,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/posts\/1263\/revisions\/1265"}],"wp:attachment":[{"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1263"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1263"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1263"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}