{"id":1241,"date":"2025-01-29T14:54:53","date_gmt":"2025-01-29T05:54:53","guid":{"rendered":"https:\/\/route-zero.com\/recruit\/route\/1241\/"},"modified":"2025-05-26T15:00:16","modified_gmt":"2025-05-26T06:00:16","slug":"1241","status":"publish","type":"route","link":"https:\/\/route-zero.com\/recruit\/route\/1241\/","title":{"rendered":"SQL UNION\u306e\u4f7f\u3044\u65b9\u3092\u3084\u3055\u3057\u304f\u89e3\u8aac\uff5c\u9055\u3044\u30fb\u6ce8\u610f\u70b9\u30fb\u6d3b\u7528\u4f8b\u307e\u3068\u3081"},"content":{"rendered":"<div>\n<h2>\u3042\u306a\u305f\u3082\u3053\u3093\u306a\u7d4c\u9a13\u3042\u308a\u307e\u305b\u3093\u304b\uff1f<\/h2>\n<ul>\n<li>\n<p>\u300c\u7570\u306a\u308b\u30c6\u30fc\u30d6\u30eb\u306e\u30c7\u30fc\u30bf\u3092\u4e00\u5ea6\u306b\u53d6\u5f97\u3057\u305f\u3044\u3051\u3069\u3001\u3069\u3046\u3059\u308c\u3070\u3044\u3044\u306e\u304b\u308f\u304b\u3089\u306a\u3044\u300d<\/p>\n<\/li>\n<li>\n<p>\u300cUNION\u3068UNION ALL\u306e\u9055\u3044\u304c\u3044\u307e\u3044\u3061\u30d4\u30f3\u3068\u3053\u306a\u3044\u300d<\/p>\n<\/li>\n<li>\n<p>\u300c\u7d50\u679c\u3092\u307e\u3068\u3081\u305f\u3044\u3051\u3069JOIN\u3058\u3083\u3046\u307e\u304f\u3044\u304b\u306a\u3044\u2026\u300d<\/p>\n<\/li>\n<\/ul>\n<p>SQL\u3067\u8907\u6570\u306e\u30af\u30a8\u30ea\u7d50\u679c\u3092\u4e00\u3064\u306b\u307e\u3068\u3081\u305f\u3044\u3068\u304d\u3001<strong>UNION<\/strong>\u306f\u3068\u3066\u3082\u4fbf\u5229\u306a\u69cb\u6587\u3067\u3059\u3002\u3068\u306f\u3044\u3048\u3001JOIN\u3068\u306e\u9055\u3044\u3084\u3001UNION ALL\u3068\u306e\u4f7f\u3044\u5206\u3051\u306b\u8ff7\u3046\u65b9\u3082\u591a\u3044\u306e\u3067\u306f\u306a\u3044\u3067\u3057\u3087\u3046\u304b\uff1f<\/p>\n<p>\u3053\u306e\u8a18\u4e8b\u3067\u306f\u3001<strong>SQL UNION\u306e\u57fa\u790e\u304b\u3089\u5fdc\u7528\u307e\u3067<\/strong>\u3092\u3001\u521d\u5fc3\u8005\u306b\u3082\u308f\u304b\u308a\u3084\u3059\u304f\u4e01\u5be7\u306b\u89e3\u8aac\u3057\u307e\u3059\u3002\u5b9f\u52d9\u3067\u3082\u983b\u51fa\u3059\u308b\u51e6\u7406\u306a\u306e\u3067\u3001\u3053\u3053\u3067\u3057\u3063\u304b\u308a\u7406\u89e3\u3057\u3066\u304a\u304d\u307e\u3057\u3087\u3046\uff01<\/p>\n<hr>\n<h2>SQL UNION\u306e\u57fa\u672c\u3068\u69cb\u6587<\/h2>\n<h3>\u25c6 UNION\u3068\u306f\uff1f<\/h3>\n<p>UNION\u306f\u3001<strong>\u8907\u6570\u306eSELECT\u6587\u306e\u7d50\u679c\u3092\u7e26\u306b\u307e\u3068\u3081\u308b<\/strong>\u305f\u3081\u306eSQL\u69cb\u6587\u3067\u3059\u3002<\/p>\n<pre><code>SELECT \u52171, \u52172 FROM \u30c6\u30fc\u30d6\u30ebA\r\nUNION\r\nSELECT \u52171, \u52172 FROM \u30c6\u30fc\u30d6\u30ebB;<\/code><\/pre>\n<p>\u4e0a\u8a18\u306e\u3088\u3046\u306b\u66f8\u304f\u3053\u3068\u3067\u3001\u30c6\u30fc\u30d6\u30ebA\u3068\u30c6\u30fc\u30d6\u30ebB\u306e\u540c\u3058\u69cb\u9020\u306e\u5217\u3092<strong>1\u3064\u306e\u7d50\u679c\u30bb\u30c3\u30c8\u306b\u307e\u3068\u3081\u308b<\/strong>\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n<hr>\n<h3>\u25c6 UNION\u306e\u57fa\u672c\u30eb\u30fc\u30eb<\/h3>\n<p>UNION\u3092\u4f7f\u3046\u306b\u306f\u3001\u4ee5\u4e0b\u306e\u30eb\u30fc\u30eb\u3092\u5b88\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\uff1a<\/p>\n<ul>\n<li>\n<p>\u5404SELECT\u6587\u306e<strong>\u5217\u6570\u3068\u9806\u5e8f\u304c\u4e00\u81f4\u3057\u3066\u3044\u308b\u3053\u3068<\/strong><\/p>\n<\/li>\n<li>\n<p>\u5404\u5217\u306e<strong>\u30c7\u30fc\u30bf\u578b\u304c\u4e92\u63db\u6027\u306e\u3042\u308b\u3082\u306e\u3067\u3042\u308b\u3053\u3068<\/strong><\/p>\n<\/li>\n<\/ul>\n<p><strong>POINT\uff1aSELECT\u6587\u306e\u69cb\u9020\u3092\u305d\u308d\u3048\u308b\u3053\u3068\u304c\u5927\u524d\u63d0\u3067\u3059\u3002<\/strong><\/p>\n<hr>\n<h3>\u25c6 UNION\u3068UNION ALL\u306e\u9055\u3044<\/h3>\n<p>\u521d\u5fc3\u8005\u304c\u3064\u307e\u305a\u304d\u3084\u3059\u3044\u306e\u304c\u3001<strong>UNION<\/strong>\u3068<strong>UNION ALL<\/strong>\u306e\u9055\u3044\u3067\u3059\u3002<\/p>\n<pre><code>-- \u91cd\u8907\u884c\u3092\u81ea\u52d5\u3067\u524a\u9664\r\nSELECT name FROM users\r\nUNION\r\nSELECT name FROM admins;\r\n\r\n-- \u91cd\u8907\u884c\u3082\u305d\u306e\u307e\u307e\u53d6\u5f97\r\nSELECT name FROM users\r\nUNION ALL\r\nSELECT name FROM admins;<\/code><\/pre>\n<p>\u9055\u3044\u306e\u307e\u3068\u3081<\/p>\n<ul>\n<li>\n<p>UNION \u2192 <strong>\u91cd\u8907\u884c\u3092\u81ea\u52d5\u3067\u524a\u9664<\/strong>\uff08\u51e6\u7406\u30b3\u30b9\u30c8\u304c\u3084\u3084\u9ad8\u3044\uff09<\/p>\n<\/li>\n<li>\n<p>UNION ALL \u2192 <strong>\u91cd\u8907\u884c\u3082\u542b\u3081\u3066\u3059\u3079\u3066\u8fd4\u3059<\/strong>\uff08\u9ad8\u901f\uff09<\/p>\n<\/li>\n<\/ul>\n<hr>\n<h3>\u25c6 \u8996\u899a\u7684\u306b\u7406\u89e3\u3057\u3088\u3046\uff01<\/h3>\n<pre><code>\u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510         \u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510\r\n\u2502  SELECT A   \u2502 UNION  \u2502  SELECT B   \u2502\r\n\u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518         \u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518\r\n         \u2193\uff08\u91cd\u8907\u884c\u3092\u9664\u5916\uff09\r\n       \u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510\r\n       \u2502   \u7d50\u5408\u3055\u308c\u305f\u7d50\u679c   \u2502\r\n       \u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518<\/code><\/pre>\n<pre><code>\u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510         \u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510\r\n\u2502  SELECT A   \u2502 UNION ALL \u2502  SELECT B   \u2502\r\n\u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518         \u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518\r\n         \u2193\uff08\u91cd\u8907\u884c\u3082\u542b\u3081\u3066\uff09\r\n       \u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510\r\n       \u2502   \u7d50\u5408\u3055\u308c\u305f\u7d50\u679c   \u2502\r\n       \u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518<\/code><\/pre>\n<hr>\n<h3>\u25c6 \u5b9f\u52d9\u3067\u306e\u6d3b\u7528\u4f8b\uff1a\u30a2\u30af\u30c6\u30a3\u30d3\u30c6\u30a3\u30ed\u30b0\u3092\u307e\u3068\u3081\u308b<\/h3>\n<p>\u4f8b\u3048\u3070\u3001\u30e6\u30fc\u30b6\u30fc\u3068\u7ba1\u7406\u8005\u306e\u30ed\u30b0\u30a4\u30f3\u5c65\u6b74\u30921\u3064\u306b\u307e\u3068\u3081\u305f\u3044\u5834\u5408<\/p>\n<pre><code>SELECT user_id, login_at, <span>'user'<\/span> <span>AS<\/span> role FROM user_logins\r\nUNION ALL\r\nSELECT admin_id, login_at, <span>'admin'<\/span> <span>AS<\/span> role FROM admin_logins\r\nORDER BY login_at DESC;<\/code><\/pre>\n<p>\u3053\u306e\u3088\u3046\u306b\u3059\u308c\u3070\u3001\u30ed\u30b0\u306e\u7a2e\u985e\u3092\u533a\u5225\u3057\u306a\u304c\u3089\u6642\u7cfb\u5217\u3067\u4e00\u89a7\u5316\u3067\u304d\u307e\u3059\u3002<\/p>\n<hr>\n<h2>\u3064\u307e\u305a\u304d\u3084\u3059\u3044\u30dd\u30a4\u30f3\u30c8\u3068\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9<\/h2>\n<h3>\u25c6 \u3088\u304f\u3042\u308b\u30df\u30b9\u2460\uff1a\u5217\u6570\u304c\u5408\u3063\u3066\u3044\u306a\u3044<\/h3>\n<pre><code>-- \u30a8\u30e9\u30fc\u306b\u306a\u308b\u4f8b\r\nSELECT name, email FROM users\r\nUNION\r\nSELECT name FROM admins;<\/code><\/pre>\n<p><strong>\u30a8\u30e9\u30fc\u5185\u5bb9\uff1aSELECT\u306e\u5217\u6570\u304c\u4e00\u81f4\u3057\u307e\u305b\u3093<\/strong><\/p>\n<p><strong>\u6b63\u3057\u3044\u66f8\u304d\u65b9<\/strong><\/p>\n<pre><code>SELECT name, email FROM users\r\nUNION\r\nSELECT name, <span>NULL<\/span> <span>AS<\/span> email FROM admins;<\/code><\/pre>\n<hr>\n<h3>\u25c6 \u3088\u304f\u3042\u308b\u30df\u30b9\u2461\uff1aORDER BY\u306e\u4f4d\u7f6e<\/h3>\n<pre><code>-- \u30a8\u30e9\u30fc\u306b\u306a\u308b\u4f8b\r\nSELECT name FROM users ORDER BY name\r\nUNION\r\nSELECT name FROM admins;<\/code><\/pre>\n<p>UNION\u306e\u4e2d\u3067ORDER BY\u3092\u4f7f\u3046\u5834\u5408\u306f\u3001<strong>\u6700\u5f8c\u306eSELECT\u306e\u5f8c\u306b\u307e\u3068\u3081\u3066\u8a18\u8ff0<\/strong>\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n<p><strong>\u6b63\u3057\u3044\u66f8\u304d\u65b9<\/strong><\/p>\n<pre><code>SELECT name FROM users\r\nUNION\r\nSELECT name FROM admins\r\nORDER BY name;<\/code><\/pre>\n<hr>\n<h3>\u25c6 \u3088\u304f\u3042\u308b\u8aa4\u89e3\uff1aUNION\u306fJOIN\u306e\u4ee3\u66ff\u3067\u306f\u306a\u3044<\/h3>\n<p>\u300cUNION\u3059\u308c\u3070\u30c6\u30fc\u30d6\u30eb\u306e\u60c5\u5831\u304c\u7d50\u5408\u3067\u304d\u308b\u300d\u3068\u8aa4\u89e3\u3055\u308c\u304c\u3061\u3067\u3059\u304c\u3001JOIN\u3068\u306f<strong>\u307e\u3063\u305f\u304f\u7528\u9014\u304c\u7570\u306a\u308a\u307e\u3059<\/strong>\u3002<\/p>\n<ul>\n<li>\n<p><strong>JOIN<\/strong>\uff1a\u5217\uff08\u6a2a\u65b9\u5411\uff09\u3092\u7d50\u5408<\/p>\n<\/li>\n<li>\n<p><strong>UNION<\/strong>\uff1a\u884c\uff08\u7e26\u65b9\u5411\uff09\u3092\u7d50\u5408<\/p>\n<\/li>\n<\/ul>\n<hr>\n<h3>\u25c6 \u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9<\/h3>\n<ul>\n<li>\n<p><strong>\u5927\u91cf\u30c7\u30fc\u30bf\u3092\u6271\u3046\u3068\u304d\u306fUNION ALL\u3092\u4f7f\u3046<\/strong>\uff1a\u91cd\u8907\u524a\u9664\u306e\u30b3\u30b9\u30c8\u3092\u907f\u3051\u308b<\/p>\n<\/li>\n<li>\n<p><strong>\u30c7\u30d0\u30c3\u30b0\u6642\u306fLIMIT\u3067\u7d50\u679c\u3092\u7d5e\u308b<\/strong>\uff1a\u8aa4\u3063\u305f\u7d50\u5408\u306e\u5f71\u97ff\u3092\u78ba\u8a8d\u3057\u3084\u3059\u304f\u306a\u308b<\/p>\n<\/li>\n<li>\n<p><strong>\u660e\u793a\u7684\u306b\u30ab\u30e9\u30e0\u3092\u6307\u5b9a\u3059\u308b<\/strong>\uff1aSELECT *\u306f\u907f\u3051\u308b\uff08\u69cb\u9020\u5909\u66f4\u306e\u5f71\u97ff\u3092\u53d7\u3051\u3084\u3059\u3044\uff09<\/p>\n<\/li>\n<\/ul>\n<h2>\u307e\u3068\u3081\u3068\u6b21\u306e\u30b9\u30c6\u30c3\u30d7<\/h2>\n<h3>\u25c6 \u3053\u306e\u8a18\u4e8b\u306e\u307e\u3068\u3081<\/h3>\n<ul>\n<li>\n<p><strong>UNION\u306f\u8907\u6570\u306eSELECT\u7d50\u679c\u3092\u307e\u3068\u3081\u308b\u69cb\u6587<\/strong><\/p>\n<\/li>\n<li>\n<p><strong>UNION\u306f\u91cd\u8907\u884c\u3092\u524a\u9664\u3001UNION ALL\u306f\u3059\u3079\u3066\u53d6\u5f97<\/strong><\/p>\n<\/li>\n<li>\n<p><strong>\u5217\u6570\u30fb\u30c7\u30fc\u30bf\u578b\u30fbORDER BY\u306e\u4f4d\u7f6e\u306b\u6ce8\u610f<\/strong><\/p>\n<\/li>\n<li>\n<p><strong>JOIN\u3068\u306f\u5f79\u5272\u304c\u7570\u306a\u308b\uff08\u7e26 vs \u6a2a\uff09<\/strong><\/p>\n<\/li>\n<li>\n<p><strong>\u5b9f\u52d9\u3067\u3082\u30ed\u30b0\u306e\u7d71\u5408\u3084\u4e00\u89a7\u5316\u306a\u3069\u3067\u983b\u51fa<\/strong><\/p>\n<\/li>\n<\/ul>\n<hr>\n<h3>\u30b3\u30fc\u30c9\u5b9f\u884c\u74b0\u5883\u306e\u6848\u5185<\/h3>\n<p>\u4eca\u56de\u7d39\u4ecb\u3057\u305fSQL\u306f\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u74b0\u5883\u3067\u8a66\u3059\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n<ul>\n<li>\n<p>\u30ed\u30fc\u30ab\u30eb\u306eMySQL\/PostgreSQL\u74b0\u5883<\/p>\n<\/li>\n<li>\n<p>DB\u30d6\u30e9\u30a6\u30b6 for SQLite\u306a\u3069\u306eGUI\u30c4\u30fc\u30eb<\/p>\n<\/li>\n<li>\n<p>\u30aa\u30f3\u30e9\u30a4\u30f3SQL\u5b9f\u884c\u30b5\u30fc\u30d3\u30b9\uff08\u4f8b\uff1aSQL Fiddle\u3001DB Fiddle\u306a\u3069\uff09<\/p>\n<\/li>\n<\/ul>\n<p>\u81ea\u5206\u306e\u624b\u3067\u52d5\u304b\u3057\u3066\u307f\u308b\u3053\u3068\u3067\u3001\u7406\u89e3\u304c\u3055\u3089\u306b\u6df1\u307e\u308a\u307e\u3059\u3002<\/p>\n<p>\u6700\u5f8c\u307e\u3067\u304a\u8aad\u307f\u3044\u305f\u3060\u304d\u3042\u308a\u304c\u3068\u3046\u3054\u3056\u3044\u307e\u3057\u305f\u3002<br \/>SQL\u306e\u57fa\u672c\u3092\u3057\u3063\u304b\u308a\u62bc\u3055\u3048\u308b\u3053\u3068\u304c\u3001\u5b9f\u52d9\u3067\u306e\u81ea\u4fe1\u3068\u52b9\u7387\u30a2\u30c3\u30d7\u306b\u3064\u306a\u304c\u308a\u307e\u3059\u3002UNION\u3092\u5473\u65b9\u306b\u3001\u3082\u3063\u3068\u67d4\u8edf\u306a\u30c7\u30fc\u30bf\u53d6\u5f97\u3092\u5b9f\u73fe\u3057\u307e\u3057\u3087\u3046\u3002<\/p>\n<h3>\u3010\u5916\u90e8\u30ea\u30f3\u30af\u3011<\/h3>\n<p><a href=\"https:\/\/dev.mysql.com\/doc\/refman\/8.0\/en\/union.html\" target=\"_blank\" rel=\"noopener\">MySQL\u516c\u5f0f\u30c9\u30ad\u30e5\u30e1\u30f3\u30c8\uff1aUNION<\/a><\/p>\n<p><a href=\"https:\/\/www.postgresql.jp\/document\/14\/html\/queries-union.html\" target=\"_blank\" rel=\"noopener\">PostgreSQL\u516c\u5f0f\uff1aUNION\u69cb\u6587<\/a><\/p>\n<p><a href=\"https:\/\/learn.microsoft.com\/ja-jp\/sql\/t-sql\/language-elements\/set-operators-union-transact-sql\" target=\"_blank\" rel=\"noopener\">Microsoft SQL Server: UNION (Transact-SQL)<\/a><\/p>\n<h3>\u3010\u5185\u90e8\u30ea\u30f3\u30af\u3011<\/h3>\n<p><a href=\"https:\/\/route-zero.com\/recruit\/route\/989\/\">\u3010SQL\u3011\u526f\u554f\u3044\u5408\u308f\u305b\u5165\u9580\uff5c\u57fa\u672c\u69cb\u6587\u304b\u3089\u5b9f\u4f8b\u307e\u3067\u5fb9\u5e95\u89e3\u8aac<\/a><\/p>\n<p><a href=\"https:\/\/route-zero.com\/recruit\/route\/912\/\">\u3010Docker\u5165\u9580\u3011MySQL\u74b0\u5883\u3092\u624b\u8efd\u306b\u69cb\u7bc9\u3059\u308b\u65b9\u6cd5\u3092\u5fb9\u5e95\u89e3\u8aac<\/a><\/p>\n<p><a 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