{"id":5382,"date":"2025-03-07T21:30:59","date_gmt":"2025-03-07T12:30:59","guid":{"rendered":"https:\/\/techmania.jp\/blog\/?p=5382"},"modified":"2025-08-22T15:42:48","modified_gmt":"2025-08-22T06:42:48","slug":"sql-exists","status":"publish","type":"post","link":"https:\/\/techmania.jp\/blog\/sql-exists\/","title":{"rendered":"\u3010SQL\u3011EXISTS\u53e5\u3068\u306f\uff1fEXISTS\u53e5\u306e\u69cb\u6587\u3084\u4f7f\u3044\u65b9\u3092\u8a73\u3057\u304f\u89e3\u8aac"},"content":{"rendered":"<p>\u672c\u8a18\u4e8b\u3067\u306fSQL\u3092\u5b66\u7fd2\u3057\u3066\u3044\u308b\u65b9\u306b\u5411\u3051\u3066\u3001SQL\u6587\u6cd5\u306e\u306a\u304b\u3067\u3082\u96e3\u6613\u5ea6\u306e\u9ad8\u3044\u300cEXISTS\u300d\u53e5\u306e\u57fa\u790e\u7684\u306a\u4f7f\u3044\u65b9\u304b\u3089\u5fdc\u7528\u4f8b\u3001\u985e\u4f3c\u306e\u69cb\u6587\u3068\u306e\u9055\u3044\u307e\u3067\u89e3\u8aac\u3057\u307e\u3059\u3002\u4eca\u5f8c\u306eSQL\u5b66\u7fd2\u306e\u53c2\u8003\u306b\u3057\u3066\u307f\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n\n\n<h2 id=\"outline__1\" class=\"wp-block-heading\">EXISTS\u3092\u5b66\u3076\u4e0a\u3067\u306eSQL\u306e\u4e88\u5099\u77e5\u8b58<\/h2>\n\n\n<p><span style=\"color: #0000ff;\"><span style=\"color: #000000;\"><a href=\"https:\/\/techmania.jp\/blog\/database0001\/\" target=\"_blank\" rel=\"noopener\">\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9<\/a>\u306f\u96c6\u7d04\u30fb\u6574\u7406\u3057\u305f\u30c7\u30fc\u30bf\u3092\u4fdd\u7ba1\u30fb\u7ba1\u7406\u3059\u308b\u3001\u3044\u308f\u3070\u300c\u5e33\u7c3f\u300d\u306e\u3088\u3046\u306a\u30b7\u30b9\u30c6\u30e0\u3067\u3059\u3002<a href=\"https:\/\/techmania.jp\/blog\/sql0001\/\" target=\"_blank\" rel=\"noopener\">SQL<\/a>\u306f\u305d\u306e\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306b\u30a2\u30af\u30bb\u30b9\u3057\u3066\u30c7\u30fc\u30bf\u3092\u64cd\u4f5c\u3059\u308b\u305f\u3081\u306e\u8a00\u8a9e\u3067\u3001\u30c7\u30fc\u30bf\u306e\u53d6\u5f97\u30fb\u8ffd\u52a0\u30fb\u66f4\u65b0\u30fb\u524a\u9664\u304c\u3067\u304d\u307e\u3059\u3002SQL\u306b\u306fMySQL\u3084PostgreSQL\u306a\u3069\u3055\u307e\u3056\u307e\u306a\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u7ba1\u7406\u30b7\u30b9\u30c6\u30e0\u304c\u5b58\u5728\u3057\u307e\u3059\u304c\u3001SQL\u8a00\u8a9e\u306f\u304a\u304a\u3088\u305d\u5171\u901a\u3057\u305f\u3082\u306e\u304c\u4f7f\u7528\u3055\u308c\u3066\u3044\u307e\u3059\u3002<\/span><\/span><\/p>\n<p><span style=\"color: #0000ff;\"><span style=\"color: #000000;\">\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u7ba1\u7406\u30b7\u30b9\u30c6\u30e0\u306b\u5bfe\u3059\u308b\u547d\u4ee4\u6587\u3092\u30af\u30a8\u30ea\uff08\u554f\u3044\u5408\u308f\u305b\uff09\u3068\u3044\u3044\u307e\u3059\u3002\u30af\u30a8\u30ea\u306b\u306f\u6587\uff08statement\uff09\u3001\u53e5\uff08clause\uff09\u3001\u95a2\u6570\uff08function\uff09\u306a\u3069\u306e\u5206\u985e\u3067\u3044\u304f\u3064\u3082\u306e\u30ad\u30fc\u30ef\u30fc\u30c9\u304c\u8a2d\u5b9a\u3055\u308c\u3066\u304a\u308a\u3001\u305d\u306e\u30ad\u30fc\u30ef\u30fc\u30c9\u3092\u9069\u5207\u306a\u9806\u756a\u3067\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3067\u3001\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306e\u4e2d\u304b\u3089\u5fc5\u8981\u306a\u60c5\u5831\u3092\u691c\u7d22\u3001\u53d6\u5f97\u3001\u66f4\u65b0\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/span><\/span><\/p>\n<p>\u672c\u8a18\u4e8b\u3067\u7d39\u4ecb\u3059\u308b\u300cEXISTS\u300d\u306f\u53e5\uff08clause\uff09\u3068\u3044\u3046\u7a2e\u985e\u306e\u30af\u30a8\u30ea\u3067\u3001\u300cSELECT\u300d\u306a\u3069\u306e\u5b9f\u969b\u306b\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306b\u5bfe\u3057\u3066\u884c\u3046\u51e6\u7406\u3092\u547d\u4ee4\u3059\u308b\u6587\uff08statement\uff09\u3092\u88dc\u8db3\u3059\u308b\u69cb\u6210\u8981\u7d20\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n<p><span style=\"color: #0000ff;\"><span style=\"color: #000000;\">\u300cEXISTS\u300d\u306f\u6587\u3092\u69cb\u6210\u3059\u308b\u53e5\u306e1\u3064\u306a\u306e\u3067\u3001\u305d\u308c\u3060\u3051\u3067\u547d\u4ee4\u3092\u8a18\u8ff0\u3059\u308b\u3053\u3068\u306f\u3067\u304d\u307e\u305b\u3093\u3002\u305d\u306e\u305f\u3081\u3001\u6587\u306e\u4e2d\u3067\u4f7f\u7528\u3057\u307e\u3059\u3002\u307e\u305f\u3001EXISTS\u53e5\u3092\u4f7f\u7528\u3059\u308b\u5834\u5408\u306f\u3001\u540c\u6642\u306b\u300c\u30b5\u30d6\u30af\u30a8\u30ea\u300d\u3068\u3044\u3046\u547d\u4ee4\u3092\u8a18\u8ff0\u3059\u308b\u3053\u3068\u306b\u306a\u308a\u307e\u3059\u3002<\/span><\/span><\/p>\n\n\n<h2 id=\"outline__2\" class=\"wp-block-heading\">EXISTS\u53e5\u306e\u6982\u8981\u3068\u30b5\u30d6\u30af\u30a8\u30ea\u306e\u57fa\u790e\u77e5\u8b58<\/h2>\n\n\n\n<h3 id=\"outline__2_1\" class=\"wp-block-heading\">EXISTS\u3068\u306f\uff1f<\/h3>\n\n\n<p><span style=\"color: #0000ff;\"><span style=\"color: #000000;\">SQL\u306e\u300cEXISTS\u300d\u3068\u306f\u3001\u6307\u5b9a\u3055\u308c\u305f\u6761\u4ef6\u306b\u3042\u3066\u306f\u307e\u308b\u30ec\u30b3\u30fc\u30c9\u304c\u5b58\u5728\u3059\u308b\u304b\u5426\u304b\u3092\u8abf\u3079\u308b\u306e\u306b\u4f7f\u7528\u3055\u308c\u308b\u53e5\u3067\u3059\u3002<br \/>EXISTS\u53e5\u306f\u5fc5\u305a\u30b5\u30d6\u30af\u30a8\u30ea\u3068\u4f75\u7528\u3055\u308c\u3001\u30b5\u30d6\u30af\u30a8\u30ea\u30671\u3064\u4ee5\u4e0a\u3042\u3066\u306f\u307e\u308b\u30ec\u30b3\u30fc\u30c9\u304c\u5b58\u5728\u3057\u305f\u5834\u5408\u306f\u300cTRUE\u300d\u3092\u8fd4\u3057\u3001\u305d\u3046\u3067\u306a\u3044\u5834\u5408\u306f\u300cFALSE\u300d\u3092\u8fd4\u3057\u307e\u3059\u3002<\/span><\/span><\/p>\n<p><span style=\"color: #0000ff;\"><span style=\"color: #000000;\">\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u30c6\u30fc\u30d6\u30eb\u306e\u30ab\u30e9\u30e0\u306b\u5bfe\u3057\u3066\u8907\u96d1\u306a\u6761\u4ef6\u3092\u4ed8\u3051\u3066\u30ec\u30b3\u30fc\u30c9\u3092\u53d6\u308a\u51fa\u3059\u5834\u5408\u3001\u305d\u308c\u305e\u308c\u306e\u6761\u4ef6\u306b\u5408\u308f\u305b\u3066SELECT\u6587\u3092\u8907\u6570\u56de\u4f7f\u7528\u3059\u308b\u3068\u3044\u3046\u65b9\u6cd5\u3092\u3068\u308b\u3053\u3068\u3082\u8003\u3048\u3089\u308c\u308b\u304b\u3082\u3057\u308c\u307e\u305b\u3093\u3002<br \/>\u3067\u3059\u304c\u3001\u81a8\u5927\u306a\u91cf\u306e\u30c6\u30fc\u30d6\u30eb\u30c7\u30fc\u30bf\u306e\u306a\u304b\u304b\u3089\u7279\u5b9a\u306e\u30c7\u30fc\u30bf\u3092\u51fa\u529b\u3059\u308b\u305f\u3081\u306b\u4f55\u5ea6\u3082\u540c\u3058\u3088\u3046\u306a\u51e6\u7406\u3092\u7e70\u308a\u8fd4\u3059\u306e\u306f\u52b9\u7387\u304c\u60aa\u304f\u3001\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306e\u51e6\u7406\u3082\u91cd\u304f\u306a\u308b\u306e\u3067\u3001\u826f\u3044\u30a2\u30d7\u30ed\u30fc\u30c1\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002<\/span><\/span><\/p>\n<p>\u305d\u3093\u306a\u3068\u304d\u3001EXISTS\u53e5\u3092\u4f7f\u7528\u3057\u3066\u6761\u4ef6\u3092\u7d30\u304b\u304f\u7d5e\u308a\u8fbc\u3081\u3070\u3001\u5fc5\u8981\u306a\u60c5\u5831\u3092\u52b9\u7387\u7684\u306b\u53d6\u308a\u51fa\u3059\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n<p><span style=\"color: #0000ff;\"><span style=\"color: #000000;\">\u306a\u304a\u3001\u6761\u4ef6\u4ed8\u304d\u3067\u51fa\u529b\u3092\u884c\u3046\u5834\u5408\u306fIN\u53e5\u3084JOIN\u53e5\u306a\u3069\u3092\u4f7f\u3046\u3053\u3068\u3082\u53ef\u80fd\u3067\u3059\u304c\u3001EXISTS\u3092\u4f7f\u3048\u3070\u3088\u308a\u7c21\u5358\u306b\u6761\u4ef6\u4ed8\u304d\u306eSELECT\u6587\u3092\u8a18\u8ff0\u3067\u304d\u307e\u3059\u3002<\/span><\/span><\/p>\n<p><strong>\u3010\u4f7f\u7528\u30a4\u30e1\u30fc\u30b8\u3011<\/strong><\/p>\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism line-numbers lang-sql\" data-lang=\"SQL\"><code>select * from \u30c6\u30fc\u30d6\u30ebA  \/\/\u5916\u5074\u306eSQL\nwhere exists (\n\tselect * from \u30c6\u30fc\u30d6\u30ebB  \/\/EXISTS\u5185\u306eSQL\n)<\/code><\/pre><\/div>\n\n\n<p>EXISTS\u53e5\u306f\u3001\u7279\u5b9a\u306e\u6761\u4ef6\u306b\u3042\u3066\u306f\u307e\u308b\u30ec\u30b3\u30fc\u30c9\u304c\u5b58\u5728\u3059\u308b\u304b\u5426\u304b\u3092\u8abf\u3079\u308b\u306e\u306b\u4f7f\u7528\u3055\u308c\u307e\u3059\u3002\u305d\u306e\u305f\u3081\u3001\u30b5\u30d6\u30af\u30a8\u30ea\u3067\u5177\u4f53\u7684\u306a\u5024\u3092\u8fd4\u3059\u5fc5\u8981\u306f\u306a\u304f\u3001\u5c11\u306a\u304f\u3068\u30821\u884c\u306e\u30ec\u30b3\u30fc\u30c9\u304c\u3042\u3066\u306f\u307e\u308b\u304b\u3069\u3046\u304b\u3067\u300cTRUE\u300d\u307e\u305f\u306f\u300cFALSE\u300d\u3092\u8fd4\u3059\u3060\u3051\u3067\u3059\u3002<\/p>\n<p>\u305d\u306e\u305f\u3081\u3001\u30b5\u30d6\u30af\u30a8\u30ea\u306eSELECT\u6587\u3067\u306f\u3001\u5177\u4f53\u7684\u306a\u5024\u3067\u306f\u306a\u304f\u3001\u5358\u306b\u300cSELECT *\u300d\u3084\u300cSELECT 1\u300d\u3068\u66f8\u304f\u306e\u304c\u4e00\u822c\u7684\u3067\u3059\u3002<\/p>\n\n\n<h3 id=\"outline__2_2\" class=\"wp-block-heading\">\u30b5\u30d6\u30af\u30a8\u30ea\u3068\u306f\uff1f<\/h3>\n\n\n<p>\u300c\u30b5\u30d6\u30af\u30a8\u30ea\u300d\u3068\u306f\u3001\u30e1\u30a4\u30f3\u30af\u30a8\u30ea\u5185\u306b\u30cd\u30b9\u30c8\uff08\u5165\u308c\u5b50\uff09\u3055\u308c\u305f\u30af\u30a8\u30ea\u306e\u3053\u3068\u3067\u3059\u3002SQL\u6587\u306e\u4e00\u90e8\u3068\u3057\u3066\u5185\u90e8\u3067\u5b9f\u884c\u3055\u308c\u3001\u305d\u306e\u5b9f\u884c\u7d50\u679c\u3092\u30e1\u30a4\u30f3\u30af\u30a8\u30ea\u306b\u63d0\u4f9b\u3057\u307e\u3059\u3002SELECT\u6587\u3092\u4f7f\u7528\u3059\u308b\u969b\u306b\u3088\u304f\u7528\u3044\u3089\u308c\u3001\u65e5\u672c\u8a9e\u3067\u306f\u300c\u526f\u554f\u3044\u5408\u308f\u305b\u300d\u3068\u3082\u547c\u3070\u308c\u307e\u3059\u3002\u6761\u4ef6\u3092\u6307\u5b9a\u3057\u305f\u30c7\u30fc\u30bf\u306e\u51fa\u529b\u3092\u884c\u3046\u306b\u306f\u300c\u30b5\u30d6\u30af\u30a8\u30ea\u300d\u304c\u6709\u52b9\u3067\u3059\u3002\u305f\u3068\u3048\u3070\u30013000\u4ef6\u306e\u793e\u54e1\u30c7\u30fc\u30bf\u304c\u683c\u7d0d\u3055\u308c\u3066\u3044\u308b\u30c6\u30fc\u30d6\u30eb\u304b\u3089\u300c\u5e73\u5747\u5e74\u9f62\u3088\u308a\u3082\u9ad8\u3044\u793e\u54e1\u3060\u3051\u3092\u51fa\u529b\u3059<span style=\"color: #000000;\">\u308b\u300d\u3068\u3044\u3063\u305f\u6761\u4ef6\u3092\u3064\u3051\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/span><span style=\"color: #0000ff;\"><span style=\"color: #000000;\">\u30b5\u30d6\u30af\u30a8\u30ea\u3092\u542b\u3093\u3060\u30af\u30a8\u30ea\u306f\u5148\u306b\u30b5\u30d6\u30af\u30a8\u30ea\u304b\u3089\u5b9f\u884c\u3055\u308c\u3001\u305d\u306e\u5b9f\u884c\u7d50\u679c\u3092\u4e00\u3064\u306e\u30c6\u30fc\u30d6\u30eb\u3068\u898b\u306a\u3057\u3066\u30e1\u30a4\u30f3\u30af\u30a8\u30ea\u304c\u5b9f\u884c\u3055\u308c\u307e\u3059\u3002<\/span><\/span><\/p>\n<p><strong>\u3010where\u53e5\u306e\u30b5\u30d6\u30af\u30a8\u30ea\u8a18\u8ff0\u4f8b\u3011<\/strong><\/p>\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism line-numbers lang-sql\" data-lang=\"SQL\"><code>select * from \u30c6\u30fc\u30d6\u30ebA\nwhere \u9805\u76ee &gt; (select \u9805\u76ee from \u30c6\u30fc\u30d6\u30ebB where \u6761\u4ef6);<\/code><\/pre><\/div>\n\n\n\n<h3 id=\"outline__2_3\" class=\"wp-block-heading\">\u30b5\u30d6\u30af\u30a8\u30ea\u306e\u4f7f\u7528\u4f8b<\/h3>\n\n\n<p><strong>\u3010\u58f2\u308a\u4e0a\u3052\u30c6\u30fc\u30d6\u30eb\u3011<\/strong><\/p>\n\n\n<pre class=\"wp-block-code\"><code>+------------+------------+--------+\n| \u6c0f\u540d       | \u793e\u54e1\u30b3\u30fc\u30c9 | \u58f2\u4e0a\u984d |\n+------------+------------+--------+\n| \u4f50\u85e4 \u592a\u90ce  | 10001      | 200    |\n| \u9234\u6728 \u6b21\u90ce  | 10002      | 150    |\n| \u9ad8\u6a4b \u4e09\u90ce  | 10003      | 100    |\n+------------+------------+--------+<\/code><\/pre>\n\n\n<p><strong>\u3010\u5b9f\u884c\u30af\u30a8\u30ea\u3011<\/strong><\/p>\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism line-numbers lang-sql\" data-lang=\"SQL\"><code>select \u6c0f\u540d,\u58f2\u4e0a\u984d from \u58f2\u308a\u4e0a\u3052\nwhere \u58f2\u4e0a\u984d &gt; (select AVG(\u58f2\u4e0a\u984d) from \u58f2\u308a\u4e0a\u3052);<\/code><\/pre><\/div>\n\n\n<p><strong>\u3010\u7d50\u679c\u3011<\/strong><\/p>\n\n\n<pre class=\"wp-block-code\"><code>+------------+--------+\n| \u6c0f\u540d       | \u58f2\u4e0a\u984d |\n+------------+--------+\n| \u4f50\u85e4 \u592a\u90ce  | 200    |\n+------------+--------+<\/code><\/pre>\n\n\n<p>\u307e\u305a\u3001(select AVG(\u58f2\u4e0a\u984d) from \u58f2\u308a\u4e0a\u3052) \u306e\u90e8\u5206\u3067\u793e\u5185\u5168\u54e1\u306e\u58f2\u4e0a\u984d\u306e\u5e73\u5747\u5024\u3092\u8a08\u7b97\u3057\u307e\u3059\u3002<\/p>\n<p>\u3053\u306e\u90e8\u5206\u304c\u30b5\u30d6\u30af\u30a8\u30ea\u3067\u3059\u3002<br \/>\u305d\u3057\u3066\u3001\u30e1\u30a4\u30f3\u30af\u30a8\u30ea\u3067\u5e73\u5747\u5024\u3088\u308a\u3082\u9ad8\u3044\u58f2\u4e0a\u984d\u3092\u51fa\u3057\u3066\u3044\u308b\u793e\u54e1\u3092\u8868\u793a\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n\n\n<h4 id=\"outline__2_3_1\" class=\"wp-block-heading\">\u300cselect 1\u300d\u3084\u300cselect *\u300d\u306e\u610f\u5473<\/h4>\n\n\n<p>\u5148\u307b\u3069\u306e\u8aac\u660e\u3068\u91cd\u8907\u3057\u307e\u3059\u304c\u3001\u30b5\u30d6\u30af\u30a8\u30ea\u3067\u306f\u5177\u4f53\u7684\u306a\u5024\u3067\u306f\u306a\u304f\u30011\u3064\u4ee5\u4e0a\u306e\u30ec\u30b3\u30fc\u30c9\u304c\u5b58\u5728\u3059\u308b\u304b\u5426\u304b\u3092\u8fd4\u3057\u307e\u3059\u3002\u305d\u306e\u305f\u3081\u3001\u4f55\u304b\u3057\u3089\u306e\u5024\uff08\u5f15\u6570\uff09\u3092\u5165\u308c\u308b\u5fc5\u8981\u306f\u3042\u308a\u307e\u3059\u304c\u3001\u5165\u308c\u308b\u5024\u305d\u306e\u3082\u306e\u306f\u4efb\u610f\u306e\u5024\u3067\u3044\u3044\u305f\u3081\u3001\u300c*\u300d\u3084\u300c1\u300d\u3092\u4f7f\u3046\u306e\u304c\u4e00\u822c\u7684\u3067\u3059\u3002\u305f\u3060\u3001\u30c7\u30fc\u30bf\u8aad\u307f\u8fbc\u307f\u306e\u89b3\u70b9\u304b\u3089\u3001\u300c*\u300d\u3088\u308a\u3082\u300c1\u300d\u306a\u3069\u306e\u6587\u5b57\u304c\u597d\u307e\u3057\u3044\u3068\u3055\u308c\u3066\u3044\u307e\u3059\u3002<\/p>\n\n\n<p>SELECT\u6587\u306e\u4f7f\u3044\u65b9\u306b\u3064\u3044\u3066\u306f\u3001\u3053\u3061\u3089\u306e\u8a18\u4e8b\u3067\u8a73\u3057\u304f\u89e3\u8aac\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n\n\n\n<figure class=\"wp-block-embed is-type-wp-embed is-provider-techmania wp-block-embed-techmania\"><div class=\"wp-block-embed__wrapper\">\n<blockquote class=\"wp-embedded-content\" data-secret=\"FuqecF4yuX\"><a href=\"https:\/\/techmania.jp\/blog\/sql-select\/\">\u3010SQL\u3011\u30c7\u30fc\u30bf\u3092\u62bd\u51fa\u3059\u308bSELECT\u6587\u306e\u4f7f\u3044\u65b9\u3092\u57fa\u790e\u304b\u3089\u89e3\u8aac<\/a><\/blockquote><iframe loading=\"lazy\" class=\"wp-embedded-content\" sandbox=\"allow-scripts\" security=\"restricted\" style=\"position: absolute; visibility: hidden;\" title=\"&#8220;\u3010SQL\u3011\u30c7\u30fc\u30bf\u3092\u62bd\u51fa\u3059\u308bSELECT\u6587\u306e\u4f7f\u3044\u65b9\u3092\u57fa\u790e\u304b\u3089\u89e3\u8aac&#8221; &#8212; TechMania\" src=\"https:\/\/techmania.jp\/blog\/sql-select\/embed\/#?secret=jcmTSGoR2T#?secret=FuqecF4yuX\" data-secret=\"FuqecF4yuX\" width=\"600\" height=\"338\" frameborder=\"0\" marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\"><\/iframe>\n<\/div><\/figure>\n\n\n\n<div style=\"margin-top:4%;\">\n<a href=\"https:\/\/techmania.jp\/\"><\/a><p style=\"text-align:center; text-decoration:underline black; font-weight:bold;\">\u3042\u306a\u305f\u306e<span style=\"color: red;\">\u3054\u5e0c\u671b\u306b\u6cbf\u3063\u305f\u6848\u4ef6<\/span>\u304c\u5fc5\u305a\u898b\u3064\u304b\u308a\u307e\u3059<br>\u3010\u30d5\u30ea\u30fc\u30e9\u30f3\u30b9\u5411\u3051\u3011<span style=\"color: red;\">\u9ad8\u53ce\u5165<\/span>\u30fb<span style=\"color: blue;\">\u597d\u5f85\u9047<\/span>\u306e\u6848\u4ef6\u3092\u3054\u7d39\u4ecb<\/p><\/a>\n<\/div>\n<div style=\"text-align:center; margin-top:1%;\"><a href=\"https:\/\/techmania.jp\/\"><img decoding=\"async\" style=\"filter: drop-shadow(0px 0px 3px rgba(0,0,0,0.3)); width:300px;\" alt=\"TECH MANIA \u30d5\u30ea\u30fc\u30e9\u30f3\u30b9\" src=\"https:\/\/techmania.jp\/blog\/wp-content\/uploads\/2024\/01\/fl1.png\"><\/a><\/div>\n<div>\n<a href=\"https:\/\/techmania.jp\/\"><\/a><p style=\"margin-top: 1%;text-align:center; text-decoration:underline black; font-weight:bold;\">\u226b\u307e\u305a\u306f\u7c21\u5358<span style=\"color: blue;\">60<\/span>\u79d2\u3067<span style=\"color: red;\">\u7121\u6599\u304a\u554f\u3044\u5408\u308f\u305b<\/span>\u304b\u3089\u226a<\/p><\/a>\n\n\n\n<h2 id=\"outline__3\" class=\"wp-block-heading\">EXISTS\u306e\u4f7f\u7528\u4f8b<\/h2>\n\n\n<p>\u4f8b\u3068\u3057\u3066\u30011\u3064\u4ee5\u4e0a\u306e\u5546\u54c1\u3092\u8cfc\u5165\u3057\u305f\u30e6\u30fc\u30b6\u3092\u51fa\u529b\u3057\u307e\u3059\u3002<\/p>\n<p><strong>\u3010\u30e6\u30fc\u30b6\u30c6\u30fc\u30d6\u30eb\u3011<\/strong><\/p>\n\n\n<pre class=\"wp-block-code\"><code>+------------+----------+\n| \u30e6\u30fc\u30b6\u540d   | \u30e6\u30fc\u30b6ID |\n+------------+----------+\n| \u4f50\u85e4 \u592a\u90ce  | 100001   |\n| \u9234\u6728 \u6b21\u90ce  | 100002   |\n| \u9ad8\u6a4b \u4e09\u90ce  | 100003   |\n+------------+----------+<\/code><\/pre>\n\n\n<p><strong>\u3010\u6ce8\u6587\u30c6\u30fc\u30d6\u30eb\u3011<\/strong><\/p>\n\n\n<pre class=\"wp-block-code\"><code>+----------+--------+\n| \u30e6\u30fc\u30b6ID | \u6ce8\u6587\u6570 |\n+----------+--------+\n| 100001   | 2      |\n| 100003   | 1      |\n+----------+--------+<\/code><\/pre>\n\n\n<p><strong>\u3010EXISTS\u306e\u30b5\u30f3\u30d7\u30eb\u30af\u30a8\u30ea\u3011<\/strong><\/p>\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism line-numbers lang-sql\" data-lang=\"SQL\"><code>select * from \u30e6\u30fc\u30b6\nwhere exists (select 1 from \u6ce8\u6587 where \u30e6\u30fc\u30b6.\u30e6\u30fc\u30b6ID = \u6ce8\u6587.\u30e6\u30fc\u30b6ID);<\/code><\/pre><\/div>\n\n\n<p><strong>\u30dd\u30a4\u30f3\u30c8\u2460<\/strong><\/p>\n<p>\u300c\u30e6\u30fc\u30b6.\u30e6\u30fc\u30b6ID\u300d\u300c\u6ce8\u6587.\u30e6\u30fc\u30b6ID\u300d\u3068\u3044\u3046\u8868\u8a18\u3067\u3059\u304c\u3001\u3053\u3061\u3089\u306f\u300c\u30c6\u30fc\u30d6\u30eb\u540d.\u8981\u7d20\u540d\u300d\u3068\u3044\u3046\u610f\u5473\u3067\u3001\u3069\u306e\u30c6\u30fc\u30d6\u30eb\u306e\u4f55\u306e\u9805\u76ee\u306a\u306e\u304b\u3092\u6307\u5b9a\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n<p><strong>\u30dd\u30a4\u30f3\u30c8\u2461<\/strong><\/p>\n<p>\u4e0a\u8a182\u3064\u306e\u30c6\u30fc\u30d6\u30eb\u306b\u306f\u3001\u3069\u3061\u3089\u306b\u3082\u300c\u30e6\u30fc\u30b6ID\u300d\u304c\u8a18\u5165\u3055\u308c\u3066\u3044\u307e\u3059\u3002\u30e1\u30a4\u30f3\u30af\u30a8\u30ea\u3067\u53c2\u7167\u3057\u305f\u30c6\u30fc\u30d6\u30eb\u4e0a\u306e\u5024\u304c\u30b5\u30d6\u30af\u30a8\u30ea\u3067\u53c2\u7167\u3057\u305f\u30c6\u30fc\u30d6\u30eb\u4e0a\u306e\u5024\u3068\u4e00\u81f4\u3059\u308b\u5834\u5408\u306b\u300cTRUE\u300d\u3092\u8fd4\u3057\u307e\u3059\u3002\u30c6\u30fc\u30d6\u30eb\u540c\u58eb\u306e\u7d10\u3065\u3051\u3092\u3057\u306a\u3044\u3068\u3001\u3059\u3079\u3066\u306e\u30e6\u30fc\u30b6\u304c\u8868\u793a\u3055\u308c\u3066\u3057\u307e\u3044\u307e\u3059\u3002<\/p>\n<p><strong>\u3010\u7d50\u679c\u3011<\/strong><\/p>\n\n\n<pre class=\"wp-block-code\"><code>+------------+----------+\n| \u30e6\u30fc\u30b6\u540d   | \u30e6\u30fc\u30b6ID |\n+------------+----------+\n| \u4f50\u85e4 \u592a\u90ce  | 100001   |\n| \u9ad8\u6a4b \u4e09\u90ce  | 100003   |\n+------------+----------+<\/code><\/pre>\n\n\n<p>WHERE\u4ee5\u4e0b\u306e\u6761\u4ef6\u304c\u300cTRUE\u300d\u306b\u306a\u308b\u30e6\u30fc\u30b6\u306e\u30ec\u30b3\u30fc\u30c9\u3092\u62bd\u51fa\u3057\u307e\u3059\u3002<\/p>\n<p>\u5148\u8ff0\u306e\u30dd\u30a4\u30f3\u30c8\u2461\u3067\u3082\u7d39\u4ecb\u3057\u307e\u3057\u305f\u304c\u3001\u30c6\u30fc\u30d6\u30eb\u540c\u58eb\u3092\u7d10\u3065\u3051\u308b\u304b\u5426\u304b\u3067\u51fa\u529b\u3055\u308c\u308b\u30c7\u30fc\u30bf\u304c\u7570\u306a\u308a\u307e\u3059\u3002<\/p>\n<p>\u7d10\u3065\u3051\u3092\u884c\u308f\u306a\u3044\u5834\u5408\u306f\u3001\u30b5\u30d6\u30af\u30a8\u30ea\uff08EXISTS\u306e\u5f8c\u308d\u306b\u66f8\u304b\u308c\u308b\u62ec\u5f27\u306e\u5185\u5074\u306eSQL\u30af\u30a8\u30ea\uff09\u3067\u6761\u4ef6\u306b\u3042\u3066\u306f\u307e\u308b\u5024\u304c\u5b58\u5728\u3057\u305f\u5834\u5408\u306b\u3001\u30e1\u30a4\u30f3\u30af\u30a8\u30ea\uff08\u5916\u5074\u306eSQL\u30af\u30a8\u30ea\uff09\u304c\u5b9f\u884c\u3055\u308c\u307e\u3059\u3002\u5024\u304c\u5b58\u5728\u3057\u306a\u3044\u5834\u5408\u306f\u3001\u30e1\u30a4\u30f3\u30af\u30a8\u30ea\u306f\u5b9f\u884c\u3055\u308c\u307e\u305b\u3093\u3002\u3053\u308c\u3092<strong>\u300c\u5b58\u5728\u5224\u5b9a\u300d<\/strong>\u3068\u3044\u3044\u307e\u3059\u3002<\/p>\n<p>\u4e00\u65b9\u3067\u3001\u7d10\u3065\u3051\u3092\u884c\u3046\u5834\u5408\u306f\u3001\u30e1\u30a4\u30f3\u30af\u30a8\u30ea\u304c\u5b9f\u884c\u3055\u308c\u3066\u304b\u3089\u30b5\u30d6\u30af\u30a8\u30ea\u304c\u30e1\u30a4\u30f3\u30af\u30a8\u30ea\u3092\u53c2\u7167\u3057\u3066\u5b9f\u884c\u3055\u308c\u307e\u3059\u3002\u3053\u308c\u3092<strong>\u300c\u76f8\u95a2\u526f\u554f\u5408\u305b\u300d<\/strong>\u3068\u3044\u3044\u307e\u3059\u3002<\/p>\n\n\n<h3 id=\"outline__3_1\" class=\"wp-block-heading\">EXISTS\u53e5\u306f\u3069\u3046\u3044\u3046\u3068\u304d\u306b\u4f7f\u3046\u3068\u4fbf\u5229\uff1f<\/h3>\n\n\n\n<p>SQL\u3092\u4f7f\u7528\u3059\u308b\u969b\u306b\u3001\u5b9f\u969b\u306bEXISTS\u53e5\u3092\u5229\u7528\u3059\u308b\u3053\u3068\u306b\u306a\u308b\u30b1\u30fc\u30b9\u306e\u4f8b\u3092\u6319\u3052\u3066\u307f\u307e\u3057\u305f\uff01<\/p>\n\n\n\n<p>GROUP BY\u306a\u3069\u3067\u306e\u7d5e\u308a\u8fbc\u307f\u304b\u3089\u3055\u3089\u306b\u7279\u5b9a\u306e\u6761\u4ef6\u3067\u7d5e\u308a\u8fbc\u307f\u305f\u3044\u3068\u3044\u3063\u305f\u30b1\u30fc\u30b9\u3067\u4f7f\u7528\u3059\u308b\u3053\u3068\u304c\u591a\u304f\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n<ul>\n<li>\u300c\u30e6\u30fc\u30b6\u300d\u306e\u3046\u3061\u5c11\u306a\u304f\u3068\u30821\u3064\u306e\u5546\u54c1\u3092\u8cfc\u5165\u3057\u305f\u300c\u30e6\u30fc\u30b6\u300d\u3092\u51fa\u529b\u3057\u305f\u3044<\/li>\n<li>\u300c\u793e\u54e1\u30c7\u30fc\u30bf\u300d\u306e\u3046\u3061\u300c\u90e8\u7f72\u30b3\u30fc\u30c9\u300d\u304c\u300c2\u300d\u306e\u300c\u793e\u54e1\u30ec\u30b3\u30fc\u30c9\u300d\u3092\u51fa\u529b\u3057\u305f\u3044<\/li>\n<li>\u300c\u4f01\u696d\u30c7\u30fc\u30bf\u300d\u306e\u3046\u3061\u300c\u30ab\u30c6\u30b4\u30ea\u30fc\u300d\u304c\u300cIT\u300d\u306e\u300c\u4f01\u696d\u30ec\u30b3\u30fc\u30c9\u300d\u3092\u51fa\u529b\u3057\u305f\u3044<\/li>\n<li>\u300c\u793e\u54e1\u30c7\u30fc\u30bf\u300d\u3068\u300c\u90e8\u7f72\u30c7\u30fc\u30bf\u300d\u306e\u3046\u3061\u3001\u300c\u793e\u54e1\u30c7\u30fc\u30bf\u300d\u306e\u300cID\u300d\u3068\u300c\u90e8\u7f72\u30c7\u30fc\u30bf\u300d\u306e\u300c\u793e\u54e1ID\u300d\u304c\u4e00\u81f4\u3057\u3001\u4e14\u3064\u3001\u300c\u90e8\u7f72\u30b3\u30fc\u30c9\u300d\u304c\u300c3\u300d\u306e\u300c\u793e\u54e1\u30ec\u30b3\u30fc\u30c9\u300d\u3092\u51fa\u529b\u3057\u305f\u3044<\/li>\n<\/ul>\n\n\n<h2 id=\"outline__4\" class=\"wp-block-heading\">\u5b9f\u969b\u306e\u5229\u7528\u4f8b<\/h2>\n\n\n\n<h4 id=\"outline__4_1_1\" class=\"wp-block-heading\">\u5728\u5eab\u7ba1\u7406\u30b7\u30b9\u30c6\u30e0<\/h4>\n\n\n<p>\u5728\u5eab\u7ba1\u7406\u30b7\u30b9\u30c6\u30e0\u3067\u306f\u3001EXISTS\u53e5\u3092\u7528\u3044\u308b\u3053\u3068\u3067\u3001\u30b5\u30d6\u30af\u30a8\u30ea\u3067\u300c\u5728\u5eab\u30c6\u30fc\u30d6\u30eb\u300d\u306e\u3046\u3061\u3001\u8a72\u5f53\u3059\u308b\u5546\u54c1\u5728\u5eab\u304c1\u3064\u4ee5\u4e0a\u3042\u308b\u304b\u3069\u3046\u304b\u3092\u78ba\u8a8d\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n<h4 id=\"outline__4_1_2\" class=\"wp-block-heading\">\u30c7\u30fc\u30bf\u5206\u6790<\/h4>\n\n\n<p>\u30c7\u30fc\u30bf\u5206\u6790\u3067\u306f\u3001\u7279\u5b9a\u306e\u6761\u4ef6\u3092\u6e80\u305f\u3059\u30c7\u30fc\u30bf\u304c\u3042\u308b\u304b\u3069\u3046\u304b\u3092\u8abf\u3079\u308b\u306e\u306bEXISTS\u53e5\u304c\u5229\u7528\u3055\u308c\u307e\u3059\u3002\u305f\u3068\u3048\u3070\u3001\u300c\u5546\u54c1\u8cfc\u5165\u30c6\u30fc\u30d6\u30eb\u300d\u5bfe\u8c61\u306e\u671f\u9593\u3067\u7279\u5b9a\u306e\u5546\u54c1\u3092\u8cfc\u5165\u3057\u305f\u30e6\u30fc\u30b6\u3092\u8abf\u3079\u308b\u3068\u3044\u3063\u305f\u3053\u3068\u3082\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n<h2 id=\"outline__5\" class=\"wp-block-heading\">NOT EXISTS\u53e5\u3068\u306f\uff1f<\/h2>\n\n\n<p>NOT EXISTS\u53e5\u3068\u306f\u3001EXISTS\u53e5\u3068\u53cd\u5bfe\u306e\u6a5f\u80fd\u3092\u6301\u3061\u3001\u7279\u5b9a\u306e\u6761\u4ef6\u306b\u3042\u3066\u306f\u307e\u308b\u30ec\u30b3\u30fc\u30c9\u304c\u5b58\u5728\u3057\u306a\u3044\u5834\u5408\u306b\u300cTRUE\u300d\u3092\u8fd4\u3057\u3001\u5b58\u5728\u3059\u308b\u5834\u5408\u306b\u300cFALSE\u300d\u3092\u8fd4\u3057\u307e\u3059\u3002<\/p>\n\n\n<h3 id=\"outline__5_1\" class=\"wp-block-heading\">NOT EXISTS\u306e\u4f7f\u7528\u4f8b<\/h3>\n\n\n<p><strong>\u3010\u30e6\u30fc\u30b6\u30c6\u30fc\u30d6\u30eb\u3011<\/strong><\/p>\n\n\n<pre class=\"wp-block-code\"><code>+------------+----------+\n| \u30e6\u30fc\u30b6\u540d   | \u30e6\u30fc\u30b6ID |\n+------------+----------+\n| \u4f50\u85e4 \u592a\u90ce  | 100001   |\n| \u9234\u6728 \u6b21\u90ce  | 100002   |\n| \u9ad8\u6a4b \u4e09\u90ce  | 100003   |\n+------------+----------+<\/code><\/pre>\n\n\n<p><strong>\u3010\u6ce8\u6587\u30c6\u30fc\u30d6\u30eb\u3011<\/strong><\/p>\n\n\n<pre class=\"wp-block-code\"><code>+----------+--------+\n| \u30e6\u30fc\u30b6ID | \u6ce8\u6587\u6570 |\n+----------+--------+\n| 100001   | 2      |\n| 100003   | 1      |\n+----------+--------+<\/code><\/pre>\n\n\n<p><strong>\u3010NOT EXISTS\u3092\u4f7f\u7528\u3059\u308b\u30af\u30a8\u30ea\u4f8b\u3011<\/strong><\/p>\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism line-numbers lang-sql\" data-lang=\"SQL\"><code>select * from \u30e6\u30fc\u30b6\nwhere not exists (select 1 from \u6ce8\u6587 where \u30e6\u30fc\u30b6.\u30e6\u30fc\u30b6ID = \u6ce8\u6587.\u30e6\u30fc\u30b6ID);<\/code><\/pre><\/div>\n\n\n<p><strong>\u3010\u7d50\u679c\u3011<\/strong><\/p>\n\n\n<pre class=\"wp-block-code\"><code>+------------+----------+\n| \u30e6\u30fc\u30b6\u540d   | \u30e6\u30fc\u30b6ID |\n+------------+----------+\n| \u9234\u6728 \u6b21\u90ce  | 100002   |\n+------------+----------+<\/code><\/pre>\n\n\n\n<h2 id=\"outline__6\" class=\"wp-block-heading\">EXISTS\u53e5\u3068\u985e\u4f3c\u6587\u6cd5\u306e\u6bd4\u8f03<\/h2>\n\n\n\n<h3 id=\"outline__6_1\" class=\"wp-block-heading\">EXISTS\u3068IN\u306e\u6bd4\u8f03<\/h3>\n\n\n<p>EXISTS\u53e5\u3068IN\u53e5\u306f\u3069\u3061\u3089\u3082\u30b5\u30d6\u30af\u30a8\u30ea\u3092\u6271\u3044\u307e\u3059\u304c\u3001EXISTS\u53e5\u304c\u5b58\u5728\u306e\u6709\u7121\u306e\u307f\u3092\u51fa\u529b\u3059\u308b\u306e\u306b\u5bfe\u3057\u3001IN\u53e5\u306f\u6761\u4ef6\u306b\u3042\u3066\u306f\u307e\u308b\u30b3\u30fc\u30c9\u3092\u3059\u3079\u3066\u51fa\u529b\u3057\u3001\u30e1\u30a4\u30f3\u30af\u30a8\u30ea\u3067\u5024\u3092\u6bd4\u8f03\u3057\u307e\u3059\u3002\u307e\u305f\u3001IN\u53e5\u306f\u30ab\u30e9\u30e0\u540d\u3092\u6307\u5b9a\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u304c\u3001EXISTS\u53e5\u3067\u306f\u4e0d\u8981\u3067\u3059\u3002EXISTS\u53e5\u306f\u6761\u4ef6\u306b\u3042\u3066\u306f\u307e\u308b\u30ec\u30b3\u30fc\u30c9\u304c\u5b58\u5728\u3057\u305f\u6642\u70b9\u3067\u691c\u7d22\u3092\u6253\u3061\u5207\u308b\u305f\u3081\u3001IN\u53e5\u3088\u308a\u3082\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u304c\u512a\u308c\u3066\u3044\u308b\u3068\u3044\u308f\u308c\u3066\u3044\u307e\u3059\u3002\u305d\u306e\u305f\u3081\u3001\u5177\u4f53\u7684\u306a\u5024\u3092\u6bd4\u8f03\u3059\u308b\u5834\u5408\u306fIN\u53e5\u3001\u7279\u5b9a\u306e\u6761\u4ef6\u306b\u3042\u3066\u306f\u307e\u308b\u30ec\u30b3\u30fc\u30c9\u306e\u6709\u7121\u306e\u307f\u3092\u78ba\u8a8d\u3059\u308b\u5834\u5408\u306bEXISTS\u53e5\u3092\u4f7f\u3044\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n<h3 id=\"outline__6_2\" class=\"wp-block-heading\">EXISTS\u3068JOIN\u306e\u6bd4\u8f03<\/h3>\n\n\n<p>JOIN\u53e5\u306f\u8907\u6570\u306e\u30c6\u30fc\u30d6\u30eb\u3092\u7d50\u5408\u3057\u30661\u3064\u306e\u7d50\u679c\u3092\u51fa\u529b\u3057\u307e\u3059\u304c\u3001EXISTS\u53e5\u306f\u30c6\u30fc\u30d6\u30eb\u306e\u7d50\u5408\u3092\u3057\u307e\u305b\u3093\u3002\u3088\u3063\u3066\u3001\u7d50\u5408\u7d50\u679c\u5168\u4f53\u3092\u51fa\u529b\u3055\u305b\u308b\u5834\u5408\u306fJOIN\u53e5\u3001\u7279\u5b9a\u306e\u6761\u4ef6\u306b\u3042\u3066\u306f\u307e\u308b\u30ec\u30b3\u30fc\u30c9\u306e\u6709\u7121\u306e\u307f\u3092\u77e5\u308a\u305f\u3044\u5834\u5408\u306fEXISTS\u53e5\u3092\u4f7f\u3044\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n<h3 id=\"outline__6_3\" class=\"wp-block-heading\">EXISTS\u3068\u901a\u5e38\u306e\u6bd4\u8f03\u6f14\u7b97\u5b50\u306e\u6bd4\u8f03<\/h3>\n\n\n<p>\u6bd4\u8f03\u6f14\u7b97\u5b50\u306f2\u3064\u306e\u5024\u3092\u6bd4\u8f03\u3057\u3066\u51fa\u529b\u3092\u884c\u3044\u307e\u3059\u3002\u305d\u306e\u305f\u3081\u3001\u5024\u540c\u58eb\u3092\u6bd4\u8f03\u3059\u308b\u5fc5\u8981\u304c\u3042\u308b\u5834\u5408\u306f\u6bd4\u8f03\u6f14\u7b97\u5b50\u3001\u7279\u5b9a\u306e\u6761\u4ef6\u306b\u3042\u3066\u306f\u307e\u308b\u30ec\u30b3\u30fc\u30c9\u306e\u6709\u7121\u306e\u307f\u3092\u77e5\u308a\u305f\u3044\u5834\u5408\u306fEXISTS\u53e5\u3092\u4f7f\u3044\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n<h2 id=\"outline__7\" class=\"wp-block-heading\">UPDATE\u6587\u3068\u306e\u7d44\u307f\u5408\u308f\u305b<\/h2>\n\n\n<p>\u5b9f\u306f\u3001EXISTS\u3092\u4f7f\u3046\u306e\u306fSELECT\u6587\u3060\u3051\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002\u30e1\u30a4\u30f3\u30af\u30a8\u30ea\u306bUPDATE\u6587\u3092\u7528\u3044\u308b\u3053\u3068\u3067\u3001\u8a72\u5f53\u3059\u308b\u30c7\u30fc\u30bf\u306e\u307f\u3092\u66f4\u65b0\u3059\u308b\u3053\u3068\u3082\u3067\u304d\u307e\u3059\u3002<\/p>\n<p><strong>\u3010\u69cb\u6587\u4f8b\u3011<\/strong><\/p>\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism line-numbers lang-sql\" data-lang=\"SQL\"><code>update \u30c6\u30fc\u30d6\u30eb\u540d set \u30ab\u30e9\u30e0\u540d = \u5024 where exists ( \u30b5\u30d6\u30af\u30a8\u30ea );<\/code><\/pre><\/div>\n\n\n\n<h2 id=\"outline__8\" class=\"wp-block-heading\">CASE\u5f0f\u3068\u306e\u7d44\u307f\u5408\u308f\u305b<\/h2>\n\n\n\n<p>SQL\u3067\u6761\u4ef6\u5206\u5c90\u3092\u3059\u308b\u3068\u304d\u306b\u306fCASE\u5f0f\u3092\u4f7f\u3044\u307e\u3059\u304c\u3001\u3053\u306eCASE\u5f0f\u306e\u4e2d\u3067\u3082EXISTS\u3092\u4f7f\u3046\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<p><strong>\u3010\u69cb\u6587\u4f8b\u3011<\/strong><\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism line-numbers lang-sql\" data-lang=\"SQL\"><code>case \n    when exists (\u30b5\u30d6\u30af\u30a8\u30ea1) then &#39;\u50241&#39;\n    when exists (\u30b5\u30d6\u30af\u30a8\u30ea2) then &#39;\u50242&#39;\n    ...\n    else &#39;\u4f8b\u5916\u5024&#39;<\/code><\/pre><\/div>\n\n\n\n<p>CASE\u5f0f\u306b\u3064\u3044\u3066\u306f\u4ee5\u4e0b\u306e\u8a18\u4e8b\u3067\u3082\u8a73\u3057\u304f\u89e3\u8aac\u3057\u3066\u3044\u307e\u3059\u3002\u3053\u3061\u3089\u3082\u5408\u308f\u305b\u3066\u304a\u8aad\u307f\u304f\u3060\u3055\u3044\u3002<\/p>\n\n\n\n<figure class=\"wp-block-embed is-type-wp-embed is-provider-techmania wp-block-embed-techmania\"><div class=\"wp-block-embed__wrapper\">\n<blockquote class=\"wp-embedded-content\" data-secret=\"ONWQNl8r54\"><a href=\"https:\/\/techmania.jp\/blog\/sql-case\/\">5\u5206\u3067\u308f\u304b\u308bSQL\u306e\u6761\u4ef6\u5206\u5c90\u51e6\u7406\u300cCASE\u5f0f\u300d\u306e\u4f7f\u3044\u65b9\u3010\u5b8c\u5168\u7248\u3011<\/a><\/blockquote><iframe loading=\"lazy\" class=\"wp-embedded-content\" sandbox=\"allow-scripts\" security=\"restricted\" style=\"position: absolute; visibility: hidden;\" title=\"&#8220;5\u5206\u3067\u308f\u304b\u308bSQL\u306e\u6761\u4ef6\u5206\u5c90\u51e6\u7406\u300cCASE\u5f0f\u300d\u306e\u4f7f\u3044\u65b9\u3010\u5b8c\u5168\u7248\u3011&#8221; &#8212; TechMania\" src=\"https:\/\/techmania.jp\/blog\/sql-case\/embed\/#?secret=zFbM0kW0kn#?secret=ONWQNl8r54\" data-secret=\"ONWQNl8r54\" width=\"600\" height=\"338\" frameborder=\"0\" marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\"><\/iframe>\n<\/div><\/figure>\n\n\n\n<h2 id=\"outline__9\" class=\"wp-block-heading\">EXISTS\u3092\u4f7f\u3046\u3068\u304d\u306b\u6c17\u3092\u4ed8\u3051\u308b\u3053\u3068\u306f\uff1f<\/h2>\n\n\n\n<p>\u975e\u5e38\u306b\u4fbf\u5229\u306aEXISTS\u53e5\u3067\u3059\u304c\u3001\u30af\u30a8\u30ea\u306e\u4e2d\u306b\u7d44\u307f\u8fbc\u3080\u969b\u306f\u3044\u304f\u3064\u304b\u6ce8\u610f\u3059\u3079\u304d\u30dd\u30a4\u30f3\u30c8\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h3 id=\"outline__9_1\" class=\"wp-block-heading\">\u30af\u30a8\u30ea\u3092\u5de5\u592b\u3057\u306a\u3044\u3068\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u304c\u4e0b\u304c\u308a\u3084\u3059\u3044<\/h3>\n\n\n\n<p>EXISTS\u3092\u4f7f\u7528\u3057\u3066\u30ec\u30b3\u30fc\u30c9\u306e\u6709\u7121\u3092\u78ba\u8a8d\u3059\u308b\u3068\u3001\u53c2\u7167\u3057\u305f\u30c6\u30fc\u30d6\u30eb\u306e\u7dcf\u30ec\u30b3\u30fc\u30c9\u6570\u306b\u5fdc\u3058\u3066\u6bd4\u8f03\u51e6\u7406\u304c\u5b9f\u884c\u3055\u308c\u307e\u3059\u3002\u6307\u5b9a\u3057\u305f\u6761\u4ef6\u306b\u5408\u81f4\u3059\u308b\u30ec\u30b3\u30fc\u30c9\u304c\u3042\u308c\u3070\u305d\u3053\u3067\u51e6\u7406\u306f\u7d42\u4e86\u3057\u307e\u3059\u304c\u3001\u5b58\u5728\u3057\u306a\u3044\u5834\u5408\u306f\u5168\u3066\u306e\u30ec\u30b3\u30fc\u30c9\u3092\u30c1\u30a7\u30c3\u30af\u3059\u308b\u306e\u3067\u3001\u30ec\u30b3\u30fc\u30c9\u6570\u304c\u591a\u304f\u306a\u308c\u3070\u306a\u308b\u307b\u3069\u51e6\u7406\u306f\u9045\u304f\u306a\u308a\u3084\u3059\u3044\u3068\u3044\u3046\u6b20\u70b9\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u5b9f\u969b\u306e\u30af\u30a8\u30ea\u3067\u4f7f\u7528\u3059\u308b\u5834\u5408\u306b\u306f\u9069\u5207\u306a\u30a4\u30f3\u30c7\u30c3\u30af\u30b9\u3092\u8a2d\u5b9a\u3057\u3001LIMIT\u53e5\u3067\u30c7\u30fc\u30bf\u91cf\u3092\u5236\u9650\u3059\u308b\u306a\u3069\u306e\u5de5\u592b\u3092\u3059\u308b\u3088\u3046\u306b\u610f\u8b58\u3057\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n<h3 id=\"outline__9_2\" class=\"wp-block-heading\">EXISTS\u3082\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u306e\u8106\u5f31\u6027\u306b\u3064\u306a\u304c\u308b\u5834\u5408\u304c\u3042\u308b<\/h3>\n\n\n\n<p>SQL\u306b\u306f\u300c<strong>SQL\u30a4\u30f3\u30b8\u30a7\u30af\u30b7\u30e7\u30f3<\/strong>\u300d\u3068\u3044\u3046\u30b5\u30a4\u30d0\u30fc\u653b\u6483\u306e\u624b\u6cd5\u304c\u3042\u308a\u3001\u9069\u5207\u306a\u5bfe\u7b56\u3092\u53d6\u3089\u306a\u3044\u3068\u6a5f\u5bc6\u60c5\u5831\u306e\u6d41\u51fa\u3084\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306e\u7834\u58ca\u3068\u3044\u3063\u305f\u640d\u5bb3\u3092\u53d7\u3051\u308b\u5834\u5408\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<p>EXISTS\u3092\u4f7f\u7528\u3059\u308b\u5834\u5408\u3082\u4f8b\u5916\u3067\u306f\u306a\u304f\u3001\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306b\u60c5\u5831\u3092\u5165\u529b\u3059\u308b\u969b\u306f\u8a18\u53f7\u3092\u30a8\u30b9\u30b1\u30fc\u30d7\uff08\u30d7\u30ed\u30b0\u30e9\u30e0\u306b\u304a\u3051\u308b\u5404\u7a2e\u8a18\u53f7\u306e\u6587\u5b57\u304c\u6301\u3064\u6a5f\u80fd\u3092\u55aa\u5931\u3055\u305b\u3001\u305f\u3060\u306e\u6587\u5b57\u3068\u8a8d\u8b58\u3055\u305b\u308b\u3088\u3046\u306b\u3059\u308b\u51e6\u7406\uff09\u3057\u305f\u308a\u3001\u30d7\u30ec\u30fc\u30b9\u30db\u30eb\u30c0\u30fc\uff08\u7279\u5b9a\u306e\u8a18\u53f7\u3084\u6587\u5b57\u3092\u4e8b\u524d\u306b\u5165\u308c\u3066\u304a\u304d\u3001\u5b9f\u969b\u306e\u5024\u306f\u305d\u306e\u6587\u5b57\u306b\u3042\u3068\u304b\u3089\u4ee3\u5165\u3059\u308b\u65b9\u6cd5\uff09\u3092\u7528\u3044\u305f\u308a\u3059\u308b\u306a\u3069\u306e\u5bfe\u7b56\u3092\u53d6\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u7279\u306bSQL\u30a4\u30f3\u30b8\u30a7\u30af\u30b7\u30e7\u30f3\u306b\u3088\u308b\u30b5\u30a4\u30d0\u30fc\u653b\u6483\u306f\u6bce\u5e74\u591a\u304f\u306e\u4f01\u696d\u3067\u767a\u751f\u3057\u3001\u591a\u5927\u306a\u640d\u5bb3\u3092\u4e0e\u3048\u3066\u3044\u308b\u653b\u6483\u624b\u6cd5\u3067\u3059\u3002\u696d\u52d9\u3067SQL\u3092\u4f7f\u3046\u5834\u5408\u306b\u306f\u3001\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u9762\u3082\u3057\u3063\u304b\u308a\u3068\u610f\u8b58\u3057\u3066\u304a\u304d\u305f\u3044\u3067\u3059\u306d\u3002<\/p>\n\n\n\n<h2 id=\"outline__10\" class=\"wp-block-heading\">SQL\u95a2\u9023\u8a18\u4e8b<\/h2>\n\n\n<div class=\"bgBox\">\n<ul>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql0002\/\" target=\"_blank\" rel=\"noopener\">RDB\u3092\u64cd\u4f5c\u3059\u308b\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u8a00\u8a9e<strong>\u300cSQL\u300d<\/strong>\u3068\u306f\uff1f<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/nosql-notonlysql\/\" target=\"_blank\" rel=\"noopener\">RDB\u4ee5\u5916\u306e\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u7ba1\u7406\u30b7\u30b9\u30c6\u30e0<strong>\u300cNoSQL\u300d<\/strong>\u3068\u306f\uff1f<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/post-3185\/\" target=\"_blank\" rel=\"noopener\">RDB\u7ba1\u7406\u30b7\u30b9\u30c6\u30e0<strong>\u300cMySQL\u300d<\/strong>\u3068\u306f\uff1f<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/postgresql\/\" target=\"_blank\" rel=\"noopener\">RDB\u7ba1\u7406\u30b7\u30b9\u30c6\u30e0<strong>\u300cPostgreSQL\u300d<\/strong>\u3068\u306f\uff1f<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql-server\/\" target=\"_blank\" rel=\"noopener\">RDB\u7ba1\u7406\u30b7\u30b9\u30c6\u30e0<strong>\u300cSQL Server\u300d<\/strong>\u3068\u306f\uff1f<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sqlite\/\" target=\"_blank\" rel=\"noopener\">RDB\u7ba1\u7406\u30b7\u30b9\u30c6\u30e0<strong>\u300cSQLite\u300d<\/strong>\u3068\u306f\uff1f<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql-phpmyadmin\/\" target=\"_blank\" rel=\"noopener\">\u30d6\u30e9\u30a6\u30b6\u4e0a\u3067MySQL\u3092\u7ba1\u7406\u3067\u304d\u308b<strong>\u300cphpMyAdmin\u300d<\/strong>\u3068\u306f\uff1f<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql-select\/\" target=\"_blank\" rel=\"noopener\">\u30c7\u30fc\u30bf\u3092\u62bd\u51fa\u3059\u308b<strong>\u300cSELECT\u300d<\/strong>\u6587<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql-insert\/\" target=\"_blank\" rel=\"noopener\">\u30c7\u30fc\u30bf\u3092\u8ffd\u52a0\u3059\u308b<strong>\u300cINSERT\u300d<\/strong>\u6587<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql-delete\/\" target=\"_blank\" rel=\"noopener\">\u30c7\u30fc\u30bf\u3092\u524a\u9664\u3059\u308b<strong>\u300cDELETE\u300d<\/strong>\u6587<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql-update\/\" target=\"_blank\" rel=\"noopener\">\u30c7\u30fc\u30bf\u3092\u66f4\u65b0\u3059\u308b<strong>\u300cUPDATE\u300d<\/strong>\u6587<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql-alter-table\/\" target=\"_blank\" rel=\"noopener\">\u30c6\u30fc\u30d6\u30eb\u69cb\u9020\u3092\u5909\u66f4\u3059\u308b<strong>\u300cALTER TABLE\u300d<\/strong>\u6587<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql0003\/\" target=\"_blank\" rel=\"noopener\">\u62bd\u51fa\u6761\u4ef6\u3092\u6307\u5b9a\u3059\u308b<strong>\u300cWHERE\u300d<\/strong>\u53e5<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql-having\/\" target=\"_blank\" rel=\"noopener\">\u62bd\u51fa\u6761\u4ef6\u3092\u6307\u5b9a\u3059\u308b<strong>\u300cHAVING\u300d<\/strong>\u53e5<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql0004\/\" target=\"_blank\" rel=\"noopener\">\u8907\u6570\u306e\u62bd\u51fa\u6761\u4ef6\u3092\u307e\u3068\u3081\u308b<strong>\u300cIN\u300d<\/strong>\u53e5<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql-distinct\/\" target=\"_blank\" rel=\"noopener\">\u91cd\u8907\u30ec\u30b3\u30fc\u30c9\u3092\u9664\u5916\u3059\u308b<strong>\u300cDISTINCT\u300d<\/strong><\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql0005\/\" target=\"_blank\" rel=\"noopener\">\u62bd\u51fa\u7bc4\u56f2\u3092\u6307\u5b9a\u3059\u308b<strong>\u300cBETWEEN\u300d<\/strong>\u6f14\u7b97\u5b50<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql-exists\/\" target=\"_blank\" rel=\"noopener\">\u62bd\u51fa\u6761\u4ef6\u3092\u6e80\u305f\u3059\u30ec\u30b3\u30fc\u30c9\u306e\u5b58\u5728\u306e\u6709\u7121\u3092\u8abf\u3079\u308b<strong>\u300cEXISTS\u300d<\/strong>\u53e5<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql-count\/\" target=\"_blank\" rel=\"noopener\">\u30ec\u30b3\u30fc\u30c9\u4ef6\u6570\u3092\u53d6\u5f97\u3059\u308b\u96c6\u8a08\u95a2\u6570<strong>\u300cCOUNT\u300d<\/strong>\u95a2\u6570<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql-group-by\/\" target=\"_blank\" rel=\"noopener\">\u30ec\u30b3\u30fc\u30c9\u3092\u30b0\u30eb\u30fc\u30d7\u5316\u3059\u308b<strong>\u300cGROUP BY\u300d<\/strong>\u53e5<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql-order-by\/\" target=\"_blank\" rel=\"noopener\">\u62bd\u51fa\u7d50\u679c\u3092\u4e26\u3073\u66ff\u3048\u308b<strong>\u300cORDER BY\u300d<\/strong>\u53e5<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql-join\/\" target=\"_blank\" rel=\"noopener\">\u30c6\u30fc\u30d6\u30eb\u9593\u306e\u30c7\u30fc\u30bf\u3092\u7d50\u5408\u3059\u308b<strong>\u300cJOIN\u300d<\/strong>\u53e5<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql-inner-join\/\" target=\"_blank\" rel=\"noopener\">\u5185\u90e8\u7d50\u5408<strong>\u300cINNER JOIN\u300d<\/strong>\u53e5<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql-union\/\" target=\"_blank\" rel=\"noopener\">\u62bd\u51fa\u7d50\u679c\u3092\u7d71\u5408\u3057\u3066\u8868\u793a\u3059\u308b<strong>\u300cUNION\u300d<\/strong>\u53e5<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql-like\/\" target=\"_blank\" rel=\"noopener\">\u30c7\u30fc\u30bf\u306e\u66d6\u6627\u691c\u7d22<strong>\u300cLIKE\u300d<\/strong>\u53e5<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql-limit\/\" target=\"_blank\" rel=\"noopener\">\u30c7\u30fc\u30bf\u306e\u53d6\u5f97\u4ef6\u6570\u3092\u5236\u9650\u3059\u308b<strong>\u300cLIMIT\u300d<\/strong>\u53e5<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql-case\/\" target=\"_blank\" rel=\"noopener\">\u6761\u4ef6\u5206\u5c90\u51e6\u7406<strong>\u300cCASE\u300d<\/strong>\u5f0f<\/a><\/span><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql-null\/\" target=\"_blank\" rel=\"noopener\"><strong>\u300cNULL\u300d<\/strong>\u306e\u6271\u3044\u65b9<\/a><\/span><\/li>\n<li><a href=\"https:\/\/techmania.jp\/blog\/sql-primary-key\/\" target=\"_blank\" rel=\"noopener\"><strong><span style=\"color: #000000;\">\u300c\u4e3b\u30ad\u30fc\u300d<\/span><\/strong><span style=\"color: #000000;\">\u3068\u306f\uff1f<\/span><\/a><\/li>\n<li><span style=\"color: #000000;\"><a style=\"color: #000000;\" href=\"https:\/\/techmania.jp\/blog\/sql-foreign-key\/\" target=\"_blank\" rel=\"noopener\"><strong>\u300c\u5916\u90e8\u30ad\u30fc\u300d<\/strong>\u3068\u306f\uff1f<\/a><\/span><\/li>\n<\/ul>\n<\/div>\n\n\n<h2 id=\"outline__11\" class=\"wp-block-heading\">SQL\u306e\u52c9\u5f37\u65b9\u6cd5\u306f\uff1f<\/h2>\n\n\n<p>\u66f8\u7c4d\u3084\u30a4\u30f3\u30bf\u30fc\u30cd\u30c3\u30c8\u3067\u5b66\u7fd2\u3059\u308b\u65b9\u6cd5\u304c\u3042\u308a\u307e\u3059\u3002\u6628\u4eca\u3067\u306f\u3001YouTube\u306a\u3069\u306e\u52d5\u753b\u30b5\u30a4\u30c8\u3084\u30a8\u30f3\u30b8\u30cb\u30a2\u306e\u30b3\u30df\u30e5\u30cb\u30c6\u30a3\u30b5\u30a4\u30c8\u306a\u3069\u3082\u5145\u5b9f\u3057\u3066\u3044\u3066\u591a\u304f\u306e\u60c5\u5831\u304c\u624b\u306b\u5165\u308a\u307e\u3059\u3002<br \/>\u305d\u3057\u3066\u3001\u3088\u308a\u52b9\u7387\u7684\u306b\u77e5\u8b58\u30fb\u30b9\u30ad\u30eb\u3092\u7fd2\u5f97\u3059\u308b\u306b\u306f\u3001\u77e5\u8b58\u3092\u3064\u3051\u306a\u304c\u3089\u5b9f\u969b\u306b\u624b\u3092\u52d5\u304b\u3057\u3066\u307f\u308b\u306a\u3069\u3001\u30a4\u30f3\u30d7\u30c3\u30c8\u3068\u30a2\u30a6\u30c8\u30d7\u30c3\u30c8\u3092\u7e70\u308a\u8fd4\u3057\u3066\u3044\u304f\u3053\u3068\u304c\u91cd\u8981\u3067\u3059\u3002\u7279\u306b\u72ec\u5b66\u306e\u5834\u5408\u306f\u3001\u6709\u8b58\u8005\u306b\u8cea\u554f\u304c\u3067\u304d\u305f\u308a\u30d5\u30a3\u30fc\u30c9\u30d0\u30c3\u30af\u3092\u3082\u3089\u3048\u308b\u3088\u3046\u306a\u74b0\u5883\u304c\u3042\u308b\u3068\u3001\u7406\u89e3\u5ea6\u304c\u6df1\u307e\u308b\u3067\u3057\u3087\u3046\u3002<\/p>\n<p>\u305f\u3060\u3001SQL\u306b\u9650\u3089\u305a\u3001IT\u30b9\u30ad\u30eb\u3092\u8eab\u306b\u3064\u3051\u308b\u969b\u3001\u3069\u3046\u3057\u3066\u3082\u8ab2\u984c\u306b\u3076\u3064\u304b\u3063\u3066\u3057\u307e\u3046\u3053\u3068\u306f\u3042\u308a\u307e\u3059\u3088\u306d\u3002\u7279\u306b\u72ec\u5b66\u3060\u3068\u3001\u308f\u304b\u3089\u306a\u3044\u90e8\u5206\u3092\u30d7\u30ed\u306b\u8cea\u554f\u3067\u304d\u308b\u6a5f\u4f1a\u3092\u78ba\u4fdd\u3057\u306b\u304f\u304f\u3001\u30e2\u30c1\u30d9\u30fc\u30b7\u30e7\u30f3\u304c\u7d9a\u304d\u306b\u304f\u3044\u3068\u3044\u3046\u5074\u9762\u304c\u3042\u308a\u307e\u3059\u3002\u72ec\u5b66\u3067\u30e2\u30c1\u30d9\u30fc\u30b7\u30e7\u30f3\u3092\u7dad\u6301\u3059\u308b\u81ea\u4fe1\u304c\u306a\u3044\u4eba\u306b\u306f\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0\u30b9\u30af\u30fc\u30eb\u3068\u3044\u3046\u624b\u3082\u3042\u308a\u307e\u3059\u3002\u8cbb\u7528\u306f\u639b\u304b\u308a\u307e\u3059\u304c\u3001\u305d\u306e\u5206\u30b9\u30ad\u30eb\u3092\u8eab\u306b\u3064\u3051\u3084\u3059\u3044\u3067\u3059\u3002\u3057\u3063\u304b\u308a\u3068\u77e5\u8b58\u30fb\u30b9\u30ad\u30eb\u3092\u7fd2\u5f97\u3057\u3066\u5b9f\u8df5\u306b\u6d3b\u304b\u3057\u305f\u3044\u3068\u3044\u3046\u4eba\u306f\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0\u30b9\u30af\u30fc\u30eb\u304c\u304a\u3059\u3059\u3081\u3067\u3059\u3002<\/p>\n<p><span class=\"markerYellow\"><strong>\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0\u30b9\u30af\u30fc\u30eb\u306a\u3089\u30c6\u30c3\u30af\u30de\u30cb\u30a2\u304c\u304a\u3059\u3059\u3081\uff01<\/strong><\/span><\/p>\n\n\n<img decoding=\"async\" src=\"https:\/\/web-img.rensa.jp.net\/rensa\/images\/techmania\/thumbnail\/images\/yuudou.png\" class=\"post-img\" alt=\"\" loading=\"lazy\">\n\n\n<p>IT\u30b9\u30ad\u30eb\u9700\u8981\u306e\u9ad8\u307e\u308a\u3068\u3068\u3082\u306b\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0\u30b9\u30af\u30fc\u30eb\u3082\u5897\u3048\u307e\u3057\u305f\u3002\u3057\u304b\u3057\u3001\u3069\u306e\u30b9\u30af\u30fc\u30eb\u306b\u901a\u3046\u3079\u304d\u304b\u8ff7\u3063\u3066\u3057\u307e\u3046\u4eba\u3082\u3044\u308b\u3067\u3057\u3087\u3046\u3002\u305d\u3093\u306a\u65b9\u306b\u306f\u30c6\u30c3\u30af\u30de\u30cb\u30a2\u3092\u304a\u3059\u3059\u3081\u3057\u307e\u3059\uff01\u3053\u308c\u307e\u3067\u591a\u304f\u306eIT\u30a8\u30f3\u30b8\u30cb\u30a2\u3092\u80b2\u6210\u30fb\u8f29\u51fa\u3057\u3066\u304d\u305f\u30c6\u30c3\u30af\u30de\u30cb\u30a2\u3067\u3082\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0\u30b9\u30af\u30fc\u30eb\u3092\u958b\u8b1b\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n<div class=\"bgBox\">\n<p><strong>\uff1c\u30c6\u30c3\u30af\u30de\u30cb\u30a2\u306e\u7279\u5fb4\uff1e<\/strong><br \/><strong>\u30fb\u305f\u3057\u304b\u306a\u80b2\u6210\u5b9f\u7e3e\u3068\u89aa\u8eab\u306a\u6559\u80b2\u3000\uff5e\u30bb\u30ab\u30f3\u30c9\u30ad\u30e3\u30ea\u30a2\u3092\u5168\u529b\u652f\u63f4\uff5e<\/strong><br \/><strong>\u30fb\u8b1b\u5e2b\u304c\u73fe\u5f79\u30a8\u30f3\u30b8\u30cb\u30a2\u3000\uff5e\u201c\u672c\u5f53\u201d\u306e\u958b\u767a\u30ce\u30a6\u30cf\u30a6\u3092\u76f4\u306b\u5b66\u3079\u308b\uff5e<\/strong><br \/><strong>\u30fb\u5c02\u5c5e\u8b1b\u5e2b\u304c\u5b66\u7fd2\u3092\u5fb9\u5e95\u30b5\u30dd\u30fc\u30c8\u3000\uff5e\u300c\u308f\u304b\u3089\u306a\u3044\u300d\u3092\u5fb9\u5e95\u89e3\u6c7a\uff5e<\/strong><br \/><strong>\u30fb\u5b9f\u52d9\u30d9\u30fc\u30b9\u3067\u30b9\u30ad\u30eb\u3092\u7fd2\u5f97\u3000\uff5e\u5b9f\u8df5\u7684\u306a\u51dd\u7e2e\u30ab\u30ea\u30ad\u30e5\u30e9\u30e0\uff5e<\/strong><\/p>\n<\/div>\n<p>\u3053\u306e\u3088\u3046\u306a\u7279\u5fb4\u3092\u6301\u3064\u30c6\u30c3\u30af\u30de\u30cb\u30a2\u306fIT\u30a8\u30f3\u30b8\u30cb\u30a2\u306e\u30b9\u30bf\u30fc\u30c8\u30e9\u30a4\u30f3\u3068\u3057\u3066\u6700\u9069\u3067\u3059\u3002<br \/>\u8a71\u3092\u805e\u304d\u305f\u3044\u30fb\u8a73\u3057\u304f\u77e5\u308a\u305f\u3044\u3068\u3044\u3046\u65b9\u306f<a href=\"https:\/\/techmania.jp\/lp\/2\" target=\"_blank\" rel=\"noopener\">\u3053\u3061\u3089<\/a>\u304b\u3089\u304a\u6c17\u8efd\u306b\u304a\u554f\u3044\u5408\u308f\u305b\u304f\u3060\u3055\u3044\u3002<\/p>\n\n\n<script type=\"application\/ld+json\">\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"FAQPage\",\n  \"mainEntity\": [{\n    \"@type\": \"Question\",\n    \"name\": \"\u30b5\u30d6\u30af\u30a8\u30ea\u3068\u306f\uff1f\",\n    \"acceptedAnswer\": {\n      \"@type\": \"Answer\",\n      \"text\": \"\u300c\u30b5\u30d6\u30af\u30a8\u30ea\u300d\u306f\u30e1\u30a4\u30f3\u30af\u30a8\u30ea\u5185\u306b\u30cd\u30b9\u30c8\uff08\u5165\u308c\u5b50\uff09\u3055\u308c\u305f\u30af\u30a8\u30ea\u306e\u3053\u3068\u3067\u3059\u3002SQL\u6587\u306e\u4e00\u90e8\u3068\u3057\u3066\u5185\u90e8\u3067\u5b9f\u884c\u3055\u308c\u3001\u305d\u306e\u5b9f\u884c\u7d50\u679c\u3092\u30e1\u30a4\u30f3\u30af\u30a8\u30ea\u306b\u63d0\u4f9b\u3057\u307e\u3059\u3002SELECT\u6587\u3092\u4f7f\u7528\u3059\u308b\u969b\u306b\u3088\u304f\u7528\u3044\u3089\u308c\u3001\u65e5\u672c\u8a9e\u3067\u306f\u300c\u526f\u554f\u3044\u5408\u308f\u305b\u300d\u3068\u3082\u547c\u3070\u308c\u307e\u3059\u3002\u6761\u4ef6\u3092\u6307\u5b9a\u3057\u305f\u30c7\u30fc\u30bf\u306e\u51fa\u529b\u3092\u884c\u3046\u306b\u306f\u300c\u30b5\u30d6\u30af\u30a8\u30ea\u300d\u304c\u6709\u52b9\u3067\u3059\u3002\u305f\u3068\u3048\u3070\u30013000\u4ef6\u306e\u793e\u54e1\u30c7\u30fc\u30bf\u304c\u683c\u7d0d\u3055\u308c\u3066\u3044\u308b\u30c6\u30fc\u30d6\u30eb\u304b\u3089\u300c\u5e73\u5747\u5e74\u9f62\u3088\u308a\u3082\u9ad8\u3044\u793e\u54e1\u3060\u3051\u3092\u51fa\u529b\u3059\u308b\u300d\u3068\u3044\u3063\u305f\u6761\u4ef6\u3092\u3064\u3051\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002\u30b5\u30d6\u30af\u30a8\u30ea\u3092\u542b\u3093\u3060\u30af\u30a8\u30ea\u306f\u5148\u306b\u30b5\u30d6\u30af\u30a8\u30ea\u304b\u3089\u5b9f\u884c\u3055\u308c\u3001\u305d\u306e\u5b9f\u884c\u7d50\u679c\u3092\u4e00\u3064\u306e\u30c6\u30fc\u30d6\u30eb\u3068\u898b\u306a\u3057\u3066\u30e1\u30a4\u30f3\u30af\u30a8\u30ea\u304c\u5b9f\u884c\u3055\u308c\u307e\u3059\u3002\"\n    }\n  },{\n    \"@type\": \"Question\",\n    \"name\": \"EXISTS\u3068\u306f\uff1f\",\n    \"acceptedAnswer\": {\n      \"@type\": \"Answer\",\n      \"text\": \"\u300cEXISTS\u300d\u3068\u306f\u3001\u6307\u5b9a\u3055\u308c\u305f\u6761\u4ef6\u306b\u3042\u3066\u306f\u307e\u308b\u30ec\u30b3\u30fc\u30c9\u304c\u5b58\u5728\u3059\u308b\u304b\u5426\u304b\u3092\u8abf\u3079\u308b\u306e\u306b\u4f7f\u7528\u3055\u308c\u308b\u69cb\u6587\u3067\u3059\u3002EXISTS\u53e5\u306f\u5fc5\u305a\u30b5\u30d6\u30af\u30a8\u30ea\u3068\u4f75\u7528\u3055\u308c\u3001\u30b5\u30d6\u30af\u30a8\u30ea\u30671\u3064\u4ee5\u4e0a\u3042\u3066\u306f\u307e\u308b\u30ec\u30b3\u30fc\u30c9\u304c\u5b58\u5728\u3057\u305f\u5834\u5408\u306f\u300cTRUE\u300d\u3092\u8fd4\u3057\u3001\u305d\u3046\u3067\u306a\u3044\u5834\u5408\u306f\u300cFALSE\u300d\u3092\u8fd4\u3057\u307e\u3059\u3002<br>\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u30c6\u30fc\u30d6\u30eb\u306e\u30ab\u30e9\u30e0\u304b\u3089\u3001\u8907\u96d1\u306a\u6761\u4ef6\u3092\u4ed8\u3051\u3066\u30ec\u30b3\u30fc\u30c9\u3092\u53d6\u308a\u51fa\u3059\u5834\u5408\u3001\u305d\u308c\u305e\u308c\u306e\u6761\u4ef6\u306b\u5408\u308f\u305b\u3066SELECT\u6587\u3092\u8907\u6570\u56de\u884c\u3046\u3068\u3044\u3046\u65b9\u6cd5\u3092\u3068\u308b\u4eba\u3082\u591a\u3044\u3067\u3057\u3087\u3046\u3002\u3057\u304b\u3057\u3001\u81a8\u5927\u306a\u91cf\u306e\u30c6\u30fc\u30d6\u30eb\u30c7\u30fc\u30bf\u306e\u306a\u304b\u304b\u3089\u7279\u5b9a\u306e\u30c7\u30fc\u30bf\u3092\u51fa\u529b\u3059\u308b\u5834\u5408\u306f\u6761\u4ef6\u4ed8\u304d\u306eSELECT\u6587\u3092\u4f7f\u3044\u305f\u3044\u3067\u3059\u3088\u306d\u3002<br>\u306a\u304a\u3001\u6761\u4ef6\u4ed8\u304d\u3067\u51fa\u529b\u3092\u884c\u3046\u5834\u5408\u306fIN\u53e5\u3084JOIN\u53e5\u306a\u3069\u3092\u4f7f\u3046\u3053\u3068\u3082\u53ef\u80fd\u3067\u3059\u304c\u3001EXISTS\u3092\u4f7f\u3048\u3070\u3088\u308a\u7c21\u5358\u306b\u6761\u4ef6\u4ed8\u304d\u306eSELECT\u6587\u3092\u8a18\u8ff0\u3067\u304d\u307e\u3059\u3002<br>EXISTS\u53e5\u306f\u7406\u89e3\u3057\u305a\u3089\u3044\u3068\u611f\u3058\u308b\u4eba\u3082\u591a\u3044\u3067\u3059\u304c\u3001\u305d\u3093\u306a\u4eba\u306f\u82f1\u5358\u8a9e\u306e\u610f\u5473\u3092\u77e5\u308b\u3053\u3068\u3067EXISTS\u53e5\u306e\u5f79\u5272\u304c\u60f3\u50cf\u3057\u3084\u3059\u304f\u306a\u308a\u3001\u7406\u89e3\u3057\u6613\u304f\u306a\u308b\u304b\u3068\u601d\u3044\u307e\u3059<br>\u300cEXISTS\u300d\u3068\u3044\u3046\u82f1\u5358\u8a9e\u306b\u306f\u300c\u5b58\u5728\u3059\u308b\u300d\u3068\u3044\u3046\u610f\u5473\u304c\u3042\u308a\u307e\u3059\u3002\u300c\u30c6\u30fc\u30d6\u30eb\u30c7\u30fc\u30bf\u306e\u3046\u3061\u3001\u6307\u5b9a\u3057\u305f\u6761\u4ef6\u306e\u30ec\u30b3\u30fc\u30c9\u304c\u300e\u5b58\u5728\u3059\u308b\u304b\u5426\u304b\u300f\u3092\u78ba\u8a8d\u3059\u308b\u300d\u3068\u3044\u3046\u50cd\u304d\u3092\u30a4\u30e1\u30fc\u30b8\u3059\u308b\u3068\u3044\u3044\u3067\u3057\u3087\u3046\u3002\"\n    }\n  },{\n    \"@type\": \"Question\",\n    \"name\": \"NOT EXISTS\u53e5\u3068\u306f\uff1f\",\n    \"acceptedAnswer\": {\n      \"@type\": \"Answer\",\n      \"text\": \"NOT EXISTS\u53e5\u3068\u306f\u3001EXISTS\u53e5\u3068\u53cd\u5bfe\u306e\u6a5f\u80fd\u3092\u6301\u3061\u3001\u7279\u5b9a\u306e\u6761\u4ef6\u306b\u3042\u3066\u306f\u307e\u308b\u30ec\u30b3\u30fc\u30c9\u304c\u5b58\u5728\u3057\u306a\u3044\u5834\u5408\u306b\u300cTRUE\u300d\u3092\u8fd4\u3057\u3001\u5b58\u5728\u3059\u308b\u5834\u5408\u306b\u300cFALSE\u300d\u3092\u3067\u308f\u304b\u308a\u3084\u3059\u304f\u306a\u308b\u3067\u3057\u3087\u3046\u3002\"\n    }\n  },{\n    \"@type\": \"Question\",\n    \"name\": \"EXISTS\u3068IN\u306e\u9055\u3044\u306f\uff1f\",\n    \"acceptedAnswer\": {\n      \"@type\": \"Answer\",\n      \"text\": \"EXISTS\u53e5\u3068IN\u53e5\u306f\u3069\u3061\u3089\u3082\u30b5\u30d6\u30af\u30a8\u30ea\u3092\u6271\u3044\u307e\u3059\u304c\u3001EXISTS\u53e5\u304c\u5b58\u5728\u306e\u6709\u7121\u306e\u307f\u3092\u51fa\u529b\u3059\u308b\u306e\u306b\u5bfe\u3057\u3001IN\u53e5\u306f\u6761\u4ef6\u306b\u3042\u3066\u306f\u307e\u308b\u30b3\u30fc\u30c9\u3092\u3059\u3079\u3066\u51fa\u529b\u3057\u3001\u30e1\u30a4\u30f3\u30af\u30a8\u30ea\u3067\u5024\u3092\u6bd4\u8f03\u3057\u307e\u3059\u3002\u307e\u305f\u3001IN\u53e5\u306f\u30ab\u30e9\u30e0\u540d\u3092\u6307\u5b9a\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u304c\u3001EXISTS\u53e5\u3067\u306f\u4e0d\u8981\u3067\u3059\u3002EXISTS\u53e5\u306f\u6761\u4ef6\u306b\u3042\u3066\u306f\u307e\u308b\u30ec\u30b3\u30fc\u30c9\u304c\u5b58\u5728\u3057\u305f\u6642\u70b9\u3067\u691c\u7d22\u3092\u6253\u3061\u5207\u308b\u305f\u3081\u3001IN\u53e5\u3088\u308a\u3082\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u304c\u512a\u308c\u3066\u3044\u308b\u3068\u3044\u308f\u308c\u3066\u3044\u307e\u3059\u3002\u305d\u306e\u305f\u3081\u3001\u5177\u4f53\u7684\u306a\u5024\u3092\u6bd4\u8f03\u3059\u308b\u5834\u5408\u306fIN\u53e5\u3001\u7279\u5b9a\u306e\u6761\u4ef6\u306b\u3042\u3066\u306f\u307e\u308b\u30ec\u30b3\u30fc\u30c9\u306e\u6709\u7121\u306e\u307f\u3092\u78ba\u8a8d\u3059\u308b\u306bEXISTS\u53e5\u3092\u4f7f\u3044\u307e\u3057\u3087\u3046\u3002\"\n    }\n  }]\n}\n<\/script>\n","protected":false},"excerpt":{"rendered":"\u672c\u8a18\u4e8b\u3067\u306fSQL\u3092\u5b66\u7fd2\u3057\u3066\u3044\u308b\u65b9\u306b\u5411\u3051\u3066\u3001SQL\u6587\u6cd5\u306e\u306a\u304b\u3067\u3082\u96e3\u6613\u5ea6\u306e\u9ad8\u3044\u300cEXISTS\u300d\u53e5\u306e\u57fa\u790e\u7684\u306a\u4f7f\u3044\u65b9\u304b\u3089\u5fdc\u7528\u4f8b\u3001\u985e\u4f3c\u306e\u69cb\u6587\u3068\u306e\u9055\u3044\u307e\u3067\u89e3\u8aac\u3057\u307e\u3059\u3002\u4eca\u5f8c\u306eSQL\u5b66\u7fd2\u306e\u53c2\u8003\u306b\u3057\u3066\u307f\u3066\u304f\u3060\u3055\u3044\u3002 EXISTS\u3092\u5b66\u3076\u4e0a\u3067\u306eSQL\u306e\u4e88\u5099\u77e5\u8b58 \u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306f\u96c6\u7d04\u30fb\u6574\u7406\u3057\u305f\u30c7\u30fc\u30bf\u3092\u4fdd\u7ba1\u30fb\u7ba1\u7406\u3059\u308b\u3001\u3044\u308f\u3070\u300c\u5e33\u7c3f\u300d\u306e\u3088\u3046\u306a\u30b7\u30b9\u30c6\u30e0\u3067\u3059\u3002SQL\u306f\u305d\u306e\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306b\u30a2\u30af\u30bb\u30b9\u3057\u3066\u30c7\u30fc\u30bf\u3092\u64cd\u4f5c\u3059\u308b\u305f\u3081\u306e\u8a00\u8a9e\u3067\u3001\u30c7\u30fc [&hellip;]","protected":false},"author":11,"featured_media":5392,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-5382","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/techmania.jp\/blog\/wp-json\/wp\/v2\/posts\/5382","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/techmania.jp\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/techmania.jp\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/techmania.jp\/blog\/wp-json\/wp\/v2\/users\/11"}],"replies":[{"embeddable":true,"href":"https:\/\/techmania.jp\/blog\/wp-json\/wp\/v2\/comments?post=5382"}],"version-history":[{"count":30,"href":"https:\/\/techmania.jp\/blog\/wp-json\/wp\/v2\/posts\/5382\/revisions"}],"predecessor-version":[{"id":9803,"href":"https:\/\/techmania.jp\/blog\/wp-json\/wp\/v2\/posts\/5382\/revisions\/9803"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/techmania.jp\/blog\/wp-json\/wp\/v2\/media\/5392"}],"wp:attachment":[{"href":"https:\/\/techmania.jp\/blog\/wp-json\/wp\/v2\/media?parent=5382"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/techmania.jp\/blog\/wp-json\/wp\/v2\/categories?post=5382"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/techmania.jp\/blog\/wp-json\/wp\/v2\/tags?post=5382"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}