{"id":1016,"date":"2021-01-25T02:54:53","date_gmt":"2021-01-24T17:54:53","guid":{"rendered":"https:\/\/skyit.biz\/?p=1016"},"modified":"2021-01-25T02:54:54","modified_gmt":"2021-01-24T17:54:54","slug":"%e7%ac%ac12%e7%ab%a0","status":"publish","type":"post","link":"https:\/\/skyit.biz\/?p=1016","title":{"rendered":"\u7b2c12\u7ae0"},"content":{"rendered":"\n<p>\u25a0\u30c7\u30ab\u30eb\u30c8\u7a4d<br>\u25bc\u7d50\u5408\u6761\u4ef6\u304c\u6307\u5b9a\u3055\u308c\u3066\u3044\u306a\u3044\u30c7\u30ab\u30eb\u30c8\u7a4d(Oracle\u7d50\u5408\u69cb\u6587)<br>SELECT * FROM EMP, DEPT;<\/p>\n\n\n\n<p>\u25bcCROSS JOIN\u53e5\u306b\u3088\u308b\u30af\u30ed\u30b9\u7d50\u5408<br>SELECT * FROM EMP CROSS JOIN DEPT;<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"565\" height=\"262\" src=\"https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_1_SQL_12C.png\" alt=\"\" class=\"wp-image-1017\" srcset=\"https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_1_SQL_12C.png 565w, https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_1_SQL_12C-300x139.png 300w\" sizes=\"auto, (max-width: 565px) 100vw, 565px\" \/><\/figure>\n\n\n\n<p>\u7b49\u4fa1\u7d50\u5408\u3068\u975e\u7b49\u4fa1\u7d50\u5408\u3067\u306f\u3001\u7d50\u5408\u6761\u4ef6\u306b\u4e00\u81f4\u3059\u308b\u884c\u3060\u3051\u304c\u7d50\u5408\u3055\u308c\u3066\u623b\u3055\u308c\u308b\u3002<br>\u5916\u90e8\u7d50\u5408\u306f\u3001\u7d50\u5408\u6761\u4ef6\u306b\u4e00\u81f4\u3057\u306a\u3044\u884c\u3082\u7d50\u5408\u305b\u305a\u306b\u623b\u3059\u3002<\/p>\n\n\n\n<p>\u25bcOracle\u7d50\u5408\u69cb\u6587\u306e\u5916\u90e8\u7d50\u5408<br>\u7d50\u5408\u6761\u4ef6\u306b\u4e00\u81f4\u3057\u306a\u3044\u884c\u3082\u7d50\u679c\u3068\u3057\u3066\u3001\u623b\u3055\u308c\u308b\u3002<br>\u4e00\u65b9\u306e\u8868\u304b\u3089\u3059\u3079\u3066\u306e\u884c\u3092\u53d6\u308a\u51fa\u3057\u3001\u4ed6\u65b9\u306e\u8868\u304b\u3089\u7d50\u5408\u6761\u4ef6\u306b\u4e00\u81f4\u3059\u308b\u884c\u3092\u7d50\u5408\u3059\u308b\u3002<br>\u4e00\u81f4\u3057\u306a\u306a\u3051\u308c\u3070\u7d50\u5408\u305b\u305a\u306b\u3001\u5024\u304c\u6b20\u843d\u3057\u305f\u307e\u307e\u884c\u304c\u623b\u3055\u308c\u308b\u3002<br>\u5916\u90e8\u7d50\u5408\u6f14\u7b97\u5b50\uff0b\u3092\u4f7f\u3046\u3002\u6761\u4ef6\u306e\u4e00\u81f4\u3057\u306a\u3044\u884c\u306e\u3042\u308b\u8868\u306e\u65b9\u306b\u6307\u5b9a\u3059\u308b\u3002<br>\u3000\u3000\u3059\u3079\u3066\u306e\u884c\u304c\u53d6\u308a\u51fa\u3055\u308c\u306a\u3044\u3002\u30c7\u30fc\u30bf\u304c\u6b20\u843d\u3057\u3066\u3044\u308b\u8868\u306e\u65b9\u306b\u6307\u5b9a\u3059\u308b\u3002<br>\u3000\u3000\u30c7\u30fc\u30bf\u304c\u6b20\u843d\u3059\u308b\u8868\u306e\u65b9\u306b\u5916\u90e8\u7d50\u5408\u6f14\u7b97\u5b50\u3092\u4ed8\u3051\u308b\u3002<br>\u5916\u90e8\u7d50\u5408\u6f14\u7b97\u5b50\u306f\u3001\u3069\u3061\u3089\u304b\u4e00\u65b9\u306e\u8868\u306b\u3060\u3051\u6307\u5b9a\u3059\u308b\u3002<\/p>\n\n\n\n<p>\u5916\u90e8\u7d50\u5408\u3067\u3001\u3059\u3079\u3066\u306e\u884c\u3092\u53d6\u308a\u51fa\u3059\u306e\u306f\u3069\u3061\u3089\u306e\u8868\u304b\uff1f\u3001\u5024\u304c\u6b20\u843d\u3059\u308b\u306e\u306f\u3069\u3061\u3089\u306e\u8868\u304b\uff1f\u306e2\u70b9\u3092\u898b\u308b\u3002<br>\u5024\u306e\u6b20\u843d\u3059\u308b\u65b9\u306e\u8868\u306b\u5916\u90e8\u7d50\u5408\u6f14\u7b97\u5b50\uff0b\u3092\u4ed8\u3051\u308b\u3002<\/p>\n\n\n\n<p>DDL\uff08\u30c7\u30fc\u30bf\u5b9a\u7fa9\uff09\u6587\u306e\u7a2e\u985e\u306f\u3001<br>CREATE TABLE<br>DROP TABLE<br>REVOKE<br>ALTER TABLE<br>GRANT<br>TRUNCATE<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"556\" height=\"286\" src=\"https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_2_SQL_12C.png\" alt=\"\" class=\"wp-image-1018\" srcset=\"https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_2_SQL_12C.png 556w, https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_2_SQL_12C-300x154.png 300w\" sizes=\"auto, (max-width: 556px) 100vw, 556px\" \/><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"556\" height=\"131\" src=\"https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_3_SQL_12C.png\" alt=\"\" class=\"wp-image-1019\" srcset=\"https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_3_SQL_12C.png 556w, https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_3_SQL_12C-300x71.png 300w\" sizes=\"auto, (max-width: 556px) 100vw, 556px\" \/><\/figure>\n\n\n\n<p>\u305d\u306e\u8868\u3092\u89aa\u8868\u3068\u3059\u308bOREIGN KEY\u5236\u7d04\u3092\u5b9a\u7fa9\u3059\u308b\u305f\u3081\u306b\u306f\u3001REFERENCES\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u6a29\u9650\u304c\u5fc5\u8981\u3067\u3042\u308b\u3002<\/p>\n\n\n\n<p>FOREIGN KEY\u5236\u7d04\u306e\u89aa\u30ad\u30fc\u5217\u3092\u524a\u9664\u306f\u3067\u304d\u306a\u3044\u3002CASCADE CONSTRAINTS\u30ad\u30fc\u30ef\u30fc\u30c9\u3092\u6307\u5b9a\u3059\u308b\u3068\u524a\u9664\u3067\u304d\u308b\u3002<br>ON DELETE CASCADE\u30aa\u30d7\u30b7\u30e7\u30f3\u306f\u3001\u7279\u5b9a\u306e\u89aa\u30ad\u30fc\u5024\uff08\u884c\uff09\u3092\u524a\u9664\u3059\u308b\u305f\u3081\u306e\u6a5f\u80fd\u3067\u3042\u308b\u3002\u5217\u306e\u524a\u9664\u306f\u3067\u304d\u306a\u3044\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"628\" height=\"257\" src=\"https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_4_SQL_12C.png\" alt=\"\" class=\"wp-image-1020\" srcset=\"https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_4_SQL_12C.png 628w, https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_4_SQL_12C-300x123.png 300w\" sizes=\"auto, (max-width: 628px) 100vw, 628px\" \/><\/figure>\n\n\n\n<p>\u65e2\u5b58\u306e\u884c\u306b\u3001NOT NULL\u5236\u7d04\u3092\u4ed8\u3051\u308b\u3053\u3068\u306f\u3067\u304d\u306a\u3044\u3002\u3060\u304c\u3001\u30c7\u30d5\u30a9\u30eb\u30c8\u5024\u3092\u6307\u5b9a\u3059\u308c\u3070\u8ffd\u52a0\u3067\u304d\u308b\u3002<\/p>\n\n\n\n<p>\u25a0SQL\u95a2\u6570\u306e\u5165\u308c\u5b50\uff08\u30cd\u30b9\u30c8\uff09\u306e\u6df1\u3055\u306b\u3064\u3044\u3066\u306f\u3001\u5358\u4e00\u884c\u95a2\u6570\u306f\u3001\u5236\u9650\u306a\u3057\u3001\u30b0\u30eb\u30fc\u30d7\u95a2\u6570\u306f\u7b2c2\u30ec\u30d9\u30eb\u307e\u3067\u3002<\/p>\n\n\n\n<p>DECODE\u306f\u3001\u3069\u306e\u6761\u4ef6\u5024\u3068\u3082\u4e00\u81f4\u3057\u306a\u3044\u6642\u306f\u3001\u30c7\u30d5\u30a9\u30eb\u30c8\u5024\uff08\u7701\u7565\u6642\u306fNULL\uff09\u3092\u623b\u3059\u3002<\/p>\n\n\n\n<p>FM\u4fee\u98fe\u5b50<br>fmDD \u3000\u30003<br>DD \u3000\u3000\u300003<br>fm\u3092\u4ed8\u3051\u308b\u3053\u3068\u3067\u3001\u5148\u884c\u30bc\u30ed\u304c\u56de\u907f\u3055\u308c\u308b\u3002<\/p>\n\n\n\n<p>\u30c7\u30d5\u30a9\u30eb\u30c8\u65e5\u4ed8\u66f8\u5f0f\u4ee5\u5916\u3067\u65e5\u4ed8\u30c7\u30fc\u30bf\u3092\u5165\u529b\u3059\u308b\u5834\u5408\u306f\u3001TO_DATE\u95a2\u6570\u3092\u4f7f\u3046\u3002<\/p>\n\n\n\n<p>\u30bb\u30fc\u30d6\u30dd\u30a4\u30f3\u30c8\u307e\u3067\u30ed\u30fc\u30eb\u30d0\u30c3\u30af\u3057\u305f\u3060\u3051\u3067\u306f\u3001\u30c8\u30e9\u30f3\u30b6\u30af\u30b7\u30e7\u30f3\u306f\u7d42\u4e86\u3057\u307e\u305b\u3093\u3002<br>\u30ed\u30fc\u30eb\u30d0\u30c3\u30af\u3067\u524a\u9664\u3055\u308c\u305f\u30bb\u30fc\u30d6\u30dd\u30a4\u30f3\u30c8\u306f\u3001\u518d\u5ea6\u30bb\u30fc\u30d6\u30dd\u30a4\u30f3\u30c8\u3068\u3057\u3066\u8a2d\u5b9a\u3067\u304d\u308b\u3002<\/p>\n\n\n\n<p>\u30b9\u30ad\u30fc\u30de\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306f\u3001<br>\u8868<br>\u30d3\u30e5\u30fc<br>\u7d22\u5f15<br>\u9806\u5e8f<br>\u30b7\u30ce\u30cb\u30e0<br>\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u30ea\u30f3\u30af<\/p>\n\n\n\n<p>\u25a0SELECT\u6587\u306eFOR UPDATE\u53e5<br>\u691c\u7d22\u3059\u308b\u30c7\u30fc\u30bf\u3092\u6392\u4ed6\u30ed\u30c3\u30af\u3057\u3001SELECT\u6587\u3067\u691c\u7d22\u3057\u305f\u5f8c\u306b\u305d\u306e\u5927\u5143\u306e\u8868\u306e\u30c7\u30fc\u30bf\u3092\u4ed6\u306e\u30bb\u30c3\u30b7\u30e7\u30f3\u304b\u3089\u66f4\u65b0\u3059\u308b\u306e\u3092\u9632\u3050\u3002<br>\u6392\u4ed6\u30ed\u30c3\u30af\u3092\u304b\u3051\u306a\u3044\u3068\u3001\u691c\u7d22\u3057\u305f\u30c7\u30fc\u30bf\u3068\u5b9f\u969b\u306e\u8868\u306e\u30c7\u30fc\u30bf\u304c\u7570\u306a\u308b\u3053\u3068\u306b\u306a\u308a\u3001\u76f4\u5f8c\u306e\u66f4\u65b0\u4f5c\u696d\u304c\u8868\u3068\u306a\u7570\u306a\u308b\u9593\u9055\u3063\u305f\u30c7\u30fc\u30bf\u306b\u57fa\u3065\u304f\u3082\u306e\u3068\u306a\u308a\u3001<br>\u4e0d\u6b63\u306a\u7d50\u679c\u3092\u3082\u305f\u3089\u3059\u3053\u3068\u306b\u306a\u308b\u3002<\/p>\n\n\n\n<p>\u5217\u30ec\u30d9\u30eb\u3068\u8868\u30ec\u30d9\u30eb\u306e\u3069\u3061\u3089\u3067\u3082\u5236\u7d04\u3092\u5b9a\u7fa9\u3067\u304d\u308b\u306e\u306f\u5916\u90e8\u30ad\u30fc\u3067\u3042\u308b\u3002<\/p>\n\n\n\n<p>\u25a0FOREIGN KEY\u5236\u7d04\u306b\u304a\u3051\u308b\u89aa\u30ad\u30fc\u306e\u524a\u9664\u30eb\u30fc\u30eb\u306b\u3064\u3044\u3066<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"641\" height=\"539\" src=\"https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_5_SQL_12C.png\" alt=\"\" class=\"wp-image-1021\" srcset=\"https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_5_SQL_12C.png 641w, https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_5_SQL_12C-300x252.png 300w\" sizes=\"auto, (max-width: 641px) 100vw, 641px\" \/><\/figure>\n\n\n\n<p>\u25a0\u671f\u9593\u30ea\u30c6\u30e9\u30eb<br>\u671f\u9593\u30c7\u30fc\u30bf\u578b<br>INTERVAL YEAR(\u6841\u6570) TO MONTH\u306e\u30ea\u30c6\u30e9\u30eb<br>\u671f\u9593\u30c7\u30fc\u30bf\u306f\u300112\u30f6\u6708\u4ee5\u4e0a\u306f\u3001\u5e74\u63db\u7b97\u3068\u306a\u308b\u3002<br>\u4f8b\u3048\u3070\u3001100\u30f6\u6708\u306e\u5834\u5408\u306f\u3001\u5e74\u63db\u7b97\u30678\u5e74\u30684\u30f6\u6708\u3068\u306a\u308a\u30018-4\u3067\u8868\u3055\u308c\u308b\u3002<br>INTERVAL DAY(\u6841\u6570) TO SECOND(\u6841\u6570)\u306e\u30ea\u30c6\u30e9\u30eb<br>\u671f\u9593\u30c7\u30fc\u30bf\u306f\u300124\u6642\u9593\u4ee5\u4e0a\u3092\u65e5\u6570\u306b\u300160\u5206\u4ee5\u4e0a\u306f\u6642\u9593\u306b\u300160\u79d2\u4ee5\u4e0a\u306f\u5206\u306b\u63db\u7b97\u3055\u308c\u308b\u3002<br>\u4f8b\u3048\u3070\u300125\u6642\u9593\u3067\u3042\u308c\u3070\u30011\u65e51\u6642\u9593\u3068\u306a\u308b\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"622\" height=\"507\" src=\"https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_6_SQL_12C.png\" alt=\"\" class=\"wp-image-1022\" srcset=\"https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_6_SQL_12C.png 622w, https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_6_SQL_12C-300x245.png 300w\" sizes=\"auto, (max-width: 622px) 100vw, 622px\" \/><\/figure>\n\n\n\n<p>\u25a0SQL\u884c\u5236\u9650<br>ORDER BY\u53e5\u304c\u6307\u5b9a\u3055\u308c\u3001WITH TIES\u6307\u5b9a\u306f\u6709\u52b9\u306e\u3068\u304d\u3001<br>\u30ab\u30a6\u30f3\u30c83\u756a\u307e\u3067\u30b9\u30ad\u30c3\u30d7\u3057\u3066\u3001\u30ab\u30a6\u30f3\u30c84\u756a\u76ee\u304b\u3089\u6570\u3048\u3066\u3001\u30ab\u30a6\u30f3\u30c87\u756a\u76ee\u307e\u3067\u3092\u62bd\u51fa\u3059\u308b\u3002<br>WITH TIES\u6307\u5b9a\u304c\u3042\u308b\u5834\u5408\u306f\u3001\u540c\u5024\u304c\u30ab\u30a6\u30f3\u30c87\u756a\u76ee\u3067\u8907\u6570\u3042\u3063\u305f\u5834\u5408\u306f\u3001\u540c\u5024\u5206\u5168\u3066\u3092\u62bd\u51fa\u3059\u308b\u3002<br>\u4f8b\u3048\u3070\u3001\u30ab\u30a6\u30f3\u30c87\u756a\u76ee\u3067\u540c\u5024\u304c\uff13\u3064\u3042\u308c\u3070\u3001\u30ab\u30a6\u30f3\u30c89\u756a\u76ee\u307e\u3067\u51fa\u529b\u3068\u306a\u308b\u3002<br>\u3088\u3063\u3066\u3001\u62bd\u51fa\u3055\u308c\u308b\u884c\u306e\u30ab\u30a6\u30f3\u30c8\u6570\u306f\u30019\u884c\u3068\u306a\u308b\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"410\" height=\"82\" src=\"https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_7_SQL_12C.png\" alt=\"\" class=\"wp-image-1023\" srcset=\"https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_7_SQL_12C.png 410w, https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_7_SQL_12C-300x60.png 300w\" sizes=\"auto, (max-width: 410px) 100vw, 410px\" \/><\/figure>\n\n\n\n<p>\u25a0DESCRIBE\u30b3\u30de\u30f3\u30c9<br>DESCRIBE\u30b3\u30de\u30f3\u30c9\u3092\u4f7f\u3044\u3001\u8868\u307e\u305f\u306f\u30d3\u30e5\u30fc\u306e\u5217\u69cb\u9020\u3092\u8868\u793a\u3067\u5165\u308b\u3002\u8868\u793a\u3055\u308c\u308b\u60c5\u5831\u306f\u4e0b\u8a18\u306e\u901a\u308a\u3002<br>\u5217\u540d<br>\u5217\u306e\u30c7\u30fc\u30bf\u578b<br>NULL\u5024\u3092\u8a31\u3059\u304b\u3069\u3046\u304b\u306e\u60c5\u5831\uff08\u7a7a\u767d\u307e\u305f\u306f\u3001NOT NULL\uff09<\/p>\n\n\n\n<p>\u25a0TO_DATE\u95a2\u6570<\/p>\n\n\n\n<p>TO_DATE\u95a2\u6570\u3067\u6587\u5b57\u30c7\u30fc\u30bf\u3092\u65e5\u4ed8\u30c7\u30fc\u30bf\u306b\u660e\u793a\u7684\u30c7\u30fc\u30bf\u578b\u5909\u63db\u3067\u304d\u308b\u3002<br>HIDATE = TO_DATE(&#8217;10-03-16&#8242;)<br>\u3060\u305f\u3001TO_DATE\u95a2\u6570\u3067\u65e5\u4ed8\u66f8\u5f0f\u3092\u7701\u7565\u3057\u3066\u3044\u308b\u306e\u3067\u3001\u30c7\u30d5\u30a9\u30eb\u30c8\u65e5\u4ed8\u66f8\u5f0fDD-MON-RR\u3067\u6587\u5b57\u30c7\u30fc\u30bf\u3092\u89e3\u6790\u3059\u308b\u3002<br>03\u304c\u6570\u5024\u3067\u3001\u65e5\u4ed8\u66f8\u5f0f\u306f\u6708\u306e\u540d\u524d\u306e\u7701\u7565\u5f62(\u4f8b\u3048\u3070\u3001JAN,MAY)\u306a\u3069\u306e\u305f\u3081\u3001\u30a8\u30e9\u30fc\u3068\u6210\u308b\u3002<\/p>\n\n\n\n<p>ENAME = 3000<br>\u6587\u5b57\u578b\u306b\u3001\u6570\u5024\u3092\u30bb\u30c3\u30c8\u3059\u308b\u3068\u3001\u6697\u9ed9\u7684\u306b\u6587\u5b57\u30c7\u30fc\u30bf\u304c&#8217;3000&#8217;\u306b\u5909\u63db\u3055\u308c\u308b\u306e\u3067\u3001\u30a8\u30e9\u30fc\u306b\u306a\u3089\u306a\u3044\u3002<\/p>\n\n\n\n<p>\u25a0DROP TABLE PURGE\u53e5<br>\u8868\u306f\u30b4\u30df\u7bb1\u3078\u306f\u79fb\u3055\u308c\u305a\u3001\u3059\u3050\u306b\u524a\u9664\u3055\u308c\u3001\u7d22\u5f15\u3082\u540c\u6642\u306b\u524a\u9664\u3055\u308c\u308b\u3002<br>\u524a\u9664\u3055\u308c\u308b\u3068\u3001\u8868\u304a\u3088\u3073\u7d22\u5f15\u304c\u4f7f\u7528\u3057\u3066\u3044\u305f\u9818\u57df\u306f\u89e3\u653e\u3055\u308c\u3001\u4ed6\u306e\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3067\u518d\u5229\u7528\u53ef\u80fd\u3068\u306a\u308b\u3002<br>\u9806\u5e8f\u306f\u3001\u4e00\u610f\u306a\u756a\u53f7\u3092\u751f\u6210\u3059\u308b\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3067\u3001\u8868\u306e\u4e3b\u30ad\u30fc\u5024\u306e\u751f\u6210\u306a\u3069\u306b\u4f7f\u308f\u308c\u308b\u3002<br>\u9806\u5e8f\u306f\u3001\u8868\u306b\u4f9d\u5b58\u3057\u306a\u3044\u3002\u9806\u5e8f\u3092\u4f7f\u3063\u3066\u3001\u4e3b\u30ad\u30fc\u3092\u751f\u6210\u3057\u305f\u8868\u3092\u524a\u9664\u3057\u3066\u3082\u3001\u9806\u5e8f\u306f\u6b8b\u308b\u3002<\/p>\n\n\n\n<p>\u25a0\u8ad6\u7406\u6f14\u7b97\u5b50NOT<br>NOT\u306f\u3001\u76f4\u5f8c\u306e\u6761\u4ef6\u306e\u7d50\u679c\u3092\u53cd\u8ee2\u3055\u305b\u308b\u3002<br>\u76f4\u5f8c\u306e\u6761\u4ef6\u5f0f\u3092\u5426\u5b9a\u5f62\u3067\u66f8\u304d\u63db\u3048\u308b\u3053\u3068\u3067\u3001NOT\u3092\u5916\u3057\u305f\u3001\u3088\u308a\u308f\u304b\u308a\u3084\u3059\u3044\u6761\u4ef6\u5f0f\u306b\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u308b\u3002<\/p>\n\n\n\n<p>NOT(A AND B) -&gt; NOT(A) OR NOT(B)<br>NOT(A OR B) -&gt; NOT(A) AND NOT(B)<\/p>\n\n\n\n<p>NOT(SAL BETWEEN 2000 AND 3000) -&gt; SAL NOT BETWEEN 2000 AND 3000<br>NOT(HIREDATE &gt;- &#8217;01-APR-81&#8242;) -&gt; HIREDATE &lt; &#8217;01-APR-81&#8242;<\/p>\n\n\n\n<p>\u25a0\u65e5\u4ed8\u578b\u3078\u6587\u5b57\u5217\u3092\u30bb\u30c3\u30c8\u3059\u308b<\/p>\n\n\n\n<p>TO_CHAR(&#8217;01-JANUARY-1981&#8242;)\u306f\u3001\u30c7\u30d5\u30a9\u30eb\u30c8\u65e5\u4ed8DD-MON-RR\u306b\u5247\u3063\u3066\u3001\u89e3\u6790\u3055\u308c\u3001\u6697\u9ed9\u7684\u306bDATE\u578b\u306b\u5909\u63db\u3055\u308c\u308b\u3002<br>\u89e3\u6790\u3067\u3001MON\u306e\u4ee3\u308f\u308a\u306bMONTH\u3001RR\u306e\u4ee3\u308f\u308a\u306bRRRR\u304c\u81ea\u52d5\u7684\u306b\u8a66\u884c\u3055\u308c\u3066\u3001\u30a8\u30e9\u30fc\u306b\u306f\u306a\u3089\u306a\u3044\u3002<br>\u3053\u306e\u9006\u3082\u81ea\u52d5\u7684\u306b\u8a66\u884c\u3055\u308c\u308b\u3002<\/p>\n\n\n\n<p>TO_CHAR(2000,&#8217;$999,99&#8242;) 2000\u3000\u30fc\uff1e\u3000$2000.00\u3068\u306a\u308a\u3001$\u304c\u5909\u63db\u3067\u304d\u305a\u30a8\u30e9\u30fc\u3068\u6210\u308b\u3002<br>SAL NUMBER(7,2)<\/p>\n\n\n\n<p>\u25a01\u3064\u306e\u5217\u3092\u524a\u9664\u3059\u308b\u6642\u306f\u3001DROP COLUMN\u53e5\u3092\u4f7f\u3046\u3002<br>\u8907\u6570\u5217\u3092\u524a\u9664\u3059\u308b\u5834\u5408\u306f\u3001DROP\u53e5\u3092\u4f7f\u3046\u3002<\/p>\n\n\n\n<p>\u25a0\u5217\u306b\u591a\u304f\u306e\u5024\u304c\u542b\u307e\u308c\u3066\u3044\u308b\u5834\u5408\u306f\u3001\u524a\u9664\u306b\u6642\u9593\u304c\u304b\u304b\u308b\u305f\u3081\u3001SET UNUSED\u3092\u4f7f\u3044\u3001\u5217\u3092\u672a\u4f7f\u7528\u5316\u3057\u3066\u304a\u304d\u3001\u30b7\u30b9\u30c6\u30e0\u306e\u8ca0\u8377\u304c\u4f4e\u3044\u3068\u304d\u306a\u3069\u306b<br>DROP UNUSED COLUMNS\u53e5\u3067\u672a\u4f7f\u7528\u5217\u3092\u524a\u9664\u3059\u308b\u3068\u3001\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3078\u306e\u60aa\u5f71\u97ff\u3092\u56de\u907f\u3067\u304d\u308b\u3002<\/p>\n\n\n\n<p>\u25a0DROP\u53e5\u307e\u305f\u306f\u3001DROP COLUMN\u53e5\u3067\u5217\u3092\u660e\u793a\u3057\u3066\u524a\u9664\u3059\u308b\u3068\u3001\u5b58\u5728\u3059\u308b\u672a\u4f7f\u7528\u5217(UNUSED)\u3082\u540c\u6642\u306b\u524a\u9664\u3055\u308c\u308b\u3002<\/p>\n\n\n\n<p>\u25a0CASCADE CONSTRAINTS\u30aa\u30d7\u30b7\u30e7\u30f3\u3092\u4f7f\u7528\u3059\u308c\u3070\u3001\u89aa\u30ad\u30fc\u3092\u524a\u9664\u3067\u304d\u308b\u3002<\/p>\n\n\n\n<p>\u25a0TRIM\u95a2\u6570<br>\u7701\u7565\u6642\u306e\u30c7\u30d5\u30a9\u30eb\u30c8\u306f\u3001BOTH<br>TRIM(0 FROM 1000) \u306f\u30010\u6587\u5b57\u3092\u5207\u6368\u3066\u308b\u306e\u3067\u30011\u304c\u623b\u308b\u3002<br>TRIM\u306f\u3001\u6587\u5b57\u3092\u5207\u308a\u6368\u3066\u308b\u3002\u6587\u5b57\u5217\u306f\u6271\u308f\u306a\u3044\u3002<br>TRIM(&#8216;OR&#8217; FROM &#8216;ACLE&#8217;)\u306f\u3001\u6587\u5b57\u5217\u3092\u5207\u6368\u3066\u3088\u3046\u3068\u3057\u3066\u3044\u308b\u306e\u3067\u3001\u30a8\u30e9\u30fc<\/p>\n\n\n\n<p>\u25a0HAVING\u53e5<br>HAVING\u53e5\u3067\u306f\u3001\u30b0\u30eb\u30fc\u30d7\u95a2\u6570\u306e\u30cd\u30b9\u30c8\u306f\u4f7f\u7528\u3067\u304d\u306a\u3044\u305f\u3081\u3001\u30a8\u30e9\u30fc\u3068\u6210\u308b\u3002<br>\u4f8b\uff09<br>HAVING MAX(COUNT(*))<br>WHERE\u53e5\u3067\u306f\u3001\u30b0\u30eb\u30fc\u30d7\u95a2\u6570\u3092\u4f7f\u3048\u306a\u3044\u3002<\/p>\n\n\n\n<p>\u25a0NOT EXISTS\u6f14\u7b97\u5b50<br>\u76f8\u95a2\u526f\u554f\u5408\u305b\u3067\u3001A\u3068B\u306e\u30c7\u30fc\u30bf\u3092\u6bd4\u8f03\u3057\u3066\u3001\u6bd4\u8f03\u3057\u3066\u6240\u5c5e\u306e\u306a\u3044\u30c7\u30fc\u30bf\u3092\u62bd\u51fa\u3059\u308b\u3002<\/p>\n\n\n\n<p>\u25a0FOREIGN KEY\u5236\u7d04\u306e\u89aa\u30ad\u30fc\u306e\u524a\u9664\u30eb\u30fc\u30eb<br>\u89aa\u30ad\u30fc\u306e\u524a\u9664\u30eb\u30fc\u30eb\u306e\u30c7\u30d5\u30a9\u30eb\u30c8\u306f\u3001\u524a\u9664\u5236\u9650\u3067\u3042\u308a\u3001\u5916\u90e8\u30ad\u30fc\u304b\u3089\u53c2\u7167\u3055\u308c\u3066\u3044\u308b\u89aa\u30ad\u30fc\u3092\u524a\u9664\u3067\u304d\u306a\u3044\u3002<br>\u30aa\u30d7\u30b7\u30e7\u30f3\u306e<br>ON DELETE CASCADE<br>ON DELETE SET NULL<br>\u3092\u4f7f\u7528\u3059\u308b\u3053\u3068\u3067\u5916\u90e8\u30ad\u30fc\u304b\u3089\u53c2\u7167\u3055\u308c\u3066\u3044\u308b\u89aa\u30ad\u30fc\u3092\u524a\u9664\u3067\u304d\u308b\u3002<\/p>\n\n\n\n<p>\u25a0LIKE\u6f14\u7b97\u5b50\u3092\u4f7f\u3063\u305f\u30ef\u30a4\u30eb\u30c9\u30ab\u30fc\u30c9\u691c\u7d22\u306b\u3064\u3044\u3066<br>\u30d1\u30fc\u30bb\u30f3\u30c8\u8a18\u53f7%\u3084\u30a2\u30f3\u30c0\u30fc\u30b9\u30b3\u30a2<em>\u3092\u4f7f\u3044\u3001\u30ef\u30a4\u30eb\u30c9\u30ab\u30fc\u30c9\u691c\u7d22\u3092\u884c\u3048\u308b\u3002 %\u3084<\/em>\u3092\u3001\u6587\u5b57\u30ea\u30c6\u30e9\u30eb\u3068\u3057\u3066\u3001\u691c\u7d22\u3059\u308b\u5834\u5408\u306b\u306f\u3001\u30a8\u30b9\u30b1\u30fc\u30d7\u6587\u5b57ESCAPE\u3092\u4f7f\u7528\u3059\u308b\u3002<br>\u30a8\u30b9\u30b1\u30fc\u30d7\u6587\u5b57ESCAPE\u306e\u6b21\u306e%\u3084_\u306f\u3001\u30ef\u30a4\u30eb\u30c9\u30ab\u30fc\u30c9\u6587\u5b57\u3067\u306f\u306a\u304f\u3001\u6587\u5b57\u30ea\u30c6\u30e9\u30eb\u3068\u3057\u3066\u6271\u308f\u308c\u308b\u3002<\/p>\n\n\n\n<p>\u30a8\u30b9\u30b1\u30fc\u30d7\u6587\u5b57\u3068\u3057\u3066\u3001E\u3092\u4f7f\u3046\u3068\u3001\u6761\u4ef6\u5f0f\u306f\u4e0b\u8a18\u306e\u901a\u308a\u3068\u306a\u308b\u3002<br>\u4f8b\uff09er_\u3092\u542b\u3080\u6587\u5b57\u5217\u3092\u691c\u7d22\u3059\u308b\u6642\u3001<br>CUSTNAME LIKE &#8216;%erE_%&#8217; ESCAPE &#8216;E&#8217;<\/p>\n\n\n\n<p>\u25a0SUM\u95a2\u6570<br>SUM\u95a2\u6570\u304a\u3088\u3073AVG\u95a2\u6570\u306f\u3001\u5f15\u6570\u3068\u3057\u3066\u6570\u5024\u30c7\u30fc\u30bf\u578b\u306e\u4ed6\u306b\u6697\u9ed9\u7684\u306b\u6570\u5024\u30c7\u30fc\u30bf\u578b\u306b\u5909\u63db\u53ef\u80fd\u306a\u6570\u5024\u4ee5\u5916\u306e\u30c7\u30fc\u30bf\u578b\u3092\u53d6\u308b\u3053\u3068\u304c\u3067\u304d\u308b\u3002<br>\u4f8b\u3048\u3070\u3001\u6587\u5b57\u578b&#8217;1234&#8217;\u3092\u6697\u9ed9\u7684\u306b\u6570\u5024\u30c7\u30fc\u30bf\u578b\u306b\u578b\u5909\u63db\u3057\u3066\u3001\u53d6\u308a\u6271\u3046\u3002<\/p>\n\n\n\n<p>COUNT(*)\u306f\u3001NULL\u5024\u3092\u542b\u3080\u5168\u884c\u6570\u3092\u53d6\u308a\u51fa\u3059\u3002<br>UNIQUE\u306f\u3001DISTINCT\u3068\u7b49\u4fa1\u3067\u3042\u308a\u3001\u5217\u306e\u91cd\u8907\u3057\u305f\u884c\u3068NULL\u5024\u306e\u884c\u3092\u9664\u3044\u305f\u884c\u6570\u3092\u623b\u3059\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"619\" height=\"333\" src=\"https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_8_SQL_12C.png\" alt=\"\" class=\"wp-image-1024\" srcset=\"https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_8_SQL_12C.png 619w, https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_8_SQL_12C-300x161.png 300w\" sizes=\"auto, (max-width: 619px) 100vw, 619px\" \/><\/figure>\n\n\n\n<p>\u25bcVARCHAR2\u306f\u3001\u30c7\u30fc\u30bf\u578b\u5b9a\u7fa9\u3067\u30b5\u30a4\u30ba\u6307\u5b9a\u3092\u7701\u7565\u3067\u304d\u306a\u3044\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"616\" height=\"515\" src=\"https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_9_SQL_12C.png\" alt=\"\" class=\"wp-image-1025\" srcset=\"https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_9_SQL_12C.png 616w, https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_9_SQL_12C-300x251.png 300w\" sizes=\"auto, (max-width: 616px) 100vw, 616px\" \/><\/figure>\n\n\n\n<p>\u25a0NVL\u95a2\u6570<br>NVL\u95a2\u6570\u306e2\u3064\u306e\u5f15\u6570\u306e\u30c7\u30fc\u30bf\u578b\u304c\u3001\u7570\u306a\u308b\u5834\u5408\u30012\u756a\u76ee\u306e\u5f15\u6570\u306e\u30c7\u30fc\u30bf\u578b\u304c1\u756a\u76ee\u306e\u5f15\u6570\u306e\u30c7\u30fc\u30bf\u578b\u306b\u6697\u9ed9\u7684\u5909\u63db\u304c\u3055\u308c\u308b\u3002<br>\u3060\u304c\u30012\u756a\u76ee\u306e\u5f15\u6570\u304c\u6587\u5b57\u5217\u3067\u30011\u756a\u76ee\u306e\u5f15\u6570\u304c\u6570\u5024\u3060\u3068\u3001\u6587\u5b57\u5217\u3092\u6570\u5024\u306b\u5909\u63db\u3067\u304d\u305a\u3001\u30a8\u30e9\u30fc\u3068\u6210\u308b\u3002\u305d\u306e\u305f\u3081\u30011\u756a\u76ee\u306e\u5f15\u6570\u3092TO_CHAR\u578b\u5909\u63db\u3059\u308b\u5fc5\u8981\u304c\u3042\u308b\u3002<\/p>\n\n\n\n<p>\u25a0NVL2\u95a2\u6570<br>NVL2\u95a2\u6570\u306e2\u756a\u76ee\u30683\u756a\u76ee\u306e\u5f15\u6570\u306e\u30c7\u30fc\u30bf\u578b\u304c\u7570\u306a\u308b\u5834\u5408\u30013\u756a\u76ee\u306e\u5f15\u6570\u306e\u30c7\u30fc\u30bf\u578b\u3092\u30012\u756a\u3081\u306e\u30c7\u30fc\u30bf\u578b\u306b\u6697\u9ed9\u7684\u5909\u63db\u304c\u3055\u308c\u308b\u3002<br>2\u756a\u76ee\u304c\u6570\u5024\u578b\u30013\u756a\u76ee\u304c\u6587\u5b57\u578b\u3060\u3068\u30012\u756a\u76ee\u3092TO_CHAR\u578b\u5909\u63db\u3059\u308b\u5fc5\u8981\u304c\u3042\u308b\u3002<\/p>\n\n\n\n<p>\u25a0LPAD https:\/\/sql-oracle.com\/?p=725<br>LPAD(\u6587\u5b57\u5217,\u6841\u6570,\u57cb\u3081\u308b\u6587\u5b57\u5217\uff09<br>\u6587\u5b57\u5217\u306e\u5de6\u5074\u304b\u3089\u6307\u5b9a\u6841\u6570\u5206\u3001\u57cb\u3081\u3066\u3044\u304f\u3002<br>SELECT LPAD(&#8216;A123&#8217;,6) ROM DUAL<br>\u6307\u5b9a\u3057\u305f\u6587\u5b57\u5217\u3092\u5de6\u304b\u30896\u6841\u306b\u306a\u308b\u307e\u3067\u3001\u7a7a\u767d\u3092\u57cb\u3081\u308b\u3002<br>\u7d50\u679c\uff09[ A123]<br>\u25a0RPAD<br>RPAD(\u6587\u5b57\u5217,\u6841\u6570,\u57cb\u3081\u308b\u6587\u5b57\u5217)<br>\u6587\u5b57\u5217\u306e\u53f3\u5074\u304b\u3089\u6307\u5b9a\u6841\u6570\u5206\u3001\u57cb\u3081\u3066\u3044\u304f\u3002<\/p>\n\n\n\n<p>SELECT RPAD(&#8216;A123&#8242;,6,&#8217;0&#8217;) FROM DUAL;<br>6\u6841\u306b\u306a\u308b\u307e\u3067\u53f3\u5074\u3092\u30bc\u30ed\u57cb\u3081\u3059\u308b\u3002<br>\u7d50\u679c\uff09A12300<\/p>\n\n\n\n<p>\u25a0ORDER BY\u53e5\u306b\u3088\u308b\u30bd\u30fc\u30c8<br>\u6607\u9806\u3067\u30bd\u30fc\u30c8\u3057\u305f\u5834\u5408\u3001\u30c7\u30d5\u30a9\u30eb\u30c8\u3067\u306f\u3001NULL\u306f\u3001\u6700\u5f8c\u306b\u8868\u793a\u3055\u308c\u308b\u3002<br>\u964d\u9806\u3067\u30bd\u30fc\u30c8\u3057\u305f\u5834\u5408\u3001\u30c7\u30d5\u30a9\u30eb\u30c8\u3067\u306f\u3001NULL\u306f\u3001\u6700\u521d\u306b\u8868\u793a\u3055\u308c\u308b\u3002<\/p>\n\n\n\n<p>ORDER BY SAL NULL LAST<br>\u660e\u793a\u7684\u306b\u6307\u5b9a\u3057\u3066\u3001\u6700\u5f8c\u306e\u884c\u306b\u8868\u793a\u3055\u305b\u308b\u3002<\/p>\n\n\n\n<p>NULL\u5024\u306f\u3001\u5927\u5c0f\u95a2\u4fc2\u306b\u304a\u3044\u3066\u306f\u3001\u7121\u9650\u5927\u3092\u610f\u5473\u3059\u308b\u3002\u3086\u3048\u306b\u6607\u9806\u8868\u793a\u3067\u306f\u3001\u6700\u5927\u5024\u306f\u6700\u5f8c\u306e\u884c\u306b\u8868\u793a\u3068\u306a\u308b\u3002<br>\u964d\u9806\u8868\u793a\u3067\u306f\u3001\u6700\u5927\u5024\u304b\u3089\u8868\u793a\u3055\u308c\u308b\u306e\u3067\u3001NULL\u306f\u3001\u6700\u521d\u306e\u884c\u306b\u8868\u793a\u3055\u308c\u308b\u3002<\/p>\n\n\n\n<p>\u6607\u9806\u306f\u3001\u968e\u6bb5\u30921\u6bb5\u30012\u6bb5\u30013\u6bb5\uff5e\u3068\u4e0a\u304c\u3063\u3066\u3044\u304f\u306e\u3067\u3001\u5c0f\u3055\u306a\u5024\u304c\u6700\u521d\u306e\u884c\u306b\u8868\u793a\u3055\u308c\u308b\u3002<br>\u964d\u9806\u306f\u3001\u968e\u6bb5\u3092\u4e00\u756a\u9ad8\u3044\u3068\u3053\u308d\u304b\u3089\u3001\u4e0b\u304c\u3063\u3066\u3044\u304f\u306e\u3067\u3001\u5927\u304d\u306a\u5024\u304c\u6700\u521d\u306e\u884c\u306b\u8868\u793a\u3055\u308c\u308b\u3002<\/p>\n\n\n\n<p>\u25a0CASE\u5f0f<br>CASE\u5f0f\u3067\u306f\u3001\u3059\u3079\u3066\u306e\u623b\u308a\u5024\u306f\u3001\u540c\u3058\u30c7\u30fc\u30bf\u578b\u3067\u306a\u3051\u308c\u3070\u306a\u3089\u306a\u3044\u3002\u7570\u306a\u308b\u5834\u5408\u306f\u3001\u30a8\u30e9\u30fc\u3068\u6210\u308b\u3002<br>\u30a8\u30e9\u30fc\u4f8b\uff09<br>SELECT CASE WHEN COMM IS NULL THEN &#8216;ZEN&#8217; ELSE COMM END FROM EMP;<br>THEN \u6587\u5b57\u5217 ELSE \u6570\u5024\u578b END\u306e\u305f\u3081\u3001\u30c7\u30fc\u30bf\u578b\u4e0d\u4e00\u81f4\u306e\u305f\u3081\u3001\u30a8\u30e9\u30fc\u3068\u6210\u308b\u3002<\/p>\n\n\n\n<p>\u25a0COALESCE\u95a2\u6570<br>\u3059\u3079\u3066\u306e\u5f15\u6570\u306f\u540c\u3058\u30c7\u30fc\u30bf\u578b\u3067\u306a\u3051\u308c\u3070\u306a\u3089\u306a\u3044\u3002<br>\u7570\u306a\u308b\u5834\u5408\u306f\u3001\u30a8\u30e9\u30fc\u3068\u6210\u308b\u3002<br>\u30a8\u30e9\u30fc\u4f8b\uff09<br>SELECT COALESCE(COMM, &#8216;NO DATE&#8217;) FROM EMP;<\/p>\n\n\n\n<p>\u25a0DECODE\u95a2\u6570 https:\/\/oreno-it.info\/archives\/3188<br>DECODE\u95a2\u6570\u306e\u623b\u308a\u5024\u306e\u30c7\u30fc\u30bf\u578b\u304c\u7570\u306a\u308b\u5834\u5408\u3001\u5148\u982d\u306e\u623b\u308a\u5730\u306e\u30c7\u30fc\u30bf\u578b\u306b\u4ed6\u306e\u623b\u308a\u5730\u304c\u6697\u9ed9\u7684\u306b\u5909\u63db\u3055\u308c\u308b\u3002<br>\u5909\u63db\u3067\u304d\u306a\u3044\u5834\u5408\u306f\u3001\u30a8\u30e9\u30fc\u3068\u6210\u308b\u3002<br>\u4f8b\uff09\u691c\u7d22\u5024\u30921\u3064\u3060\u3051\u6307\u5b9a\u3057\u305f\u5834\u5408<br>SELECT DECODE(COMM,NULL,&#8217;NO DATE&#8217;,COMM) FROM EMP;<\/p>\n\n\n\n<p>DECODE(\u5217\u540d,\u50241,\u7d50\u679c1,\u7d50\u679c2)<br>\u6307\u5b9a\u3057\u305f\u5217\u540d\u306e\u5024\u304c\u3001\u6307\u5b9a\u3057\u305f\u50241\u306e\u6642\u3001\u7d50\u679c1\u3092\u51fa\u3059\u3002\u50241\u3067\u306a\u3044\u5834\u5408\u306f\u3001\u7d50\u679c2\u3092\u51fa\u3059\u3002<\/p>\n\n\n\n<p>\u4f8b\uff09\u691c\u7d22\u5024\u3092\uff12\u3064\u6307\u5b9a\u3057\u305f\u5834\u5408<br>SELECT(COLL,0,&#8217;\u4e0d\u5408\u683c&#8217;,1,&#8217;\u5408\u683c&#8217;,&#8217;\u5bfe\u8c61\u5916&#8217;);<\/p>\n\n\n\n<p>DECODE(\u5217\u540d,\u50241,\u7d50\u679c1,\u50242,\u7d50\u679c2,\u7d50\u679c3)<\/p>\n\n\n\n<p>\u4f8b\uff09NULL\u5024\u3092\u7f6e\u63db\u3059\u308b<br>DECODE(COLL,NULL,&#8217;\u672a\u53d7\u9a13&#8217;,1,&#8217;\u53d7\u9a13&#8217;,&#8217;\u5bfe\u8c61\u5916&#8217;)<\/p>\n\n\n\n<p>\u25a0FOREIGN KEY\u5236\u7d04\u306b\u304a\u3051\u308b\u89aa\u30ad\u30fc\u524a\u9664<br>\u5916\u90e8\u30ad\u30fc\u3067\u4f7f\u7528\u3055\u308c\u3066\u3044\u308b\u89aa\u30ad\u30fc\u5024\u306e\u884c\u524a\u9664\u306f\u3067\u304d\u306a\u3044\u3002<br>\u25bc\u524a\u9664\u3059\u308b\u305f\u3081\u306e\u65b9\u6cd5<br>\u25cf\u5916\u90e8\u30ad\u30fc\u3092\u524a\u9664\u3059\u308b\u3002<br>\u5916\u90e8\u30ad\u30fc\u3067\u4f7f\u7528\u3055\u308c\u3048\u3044\u306a\u3044\u89aa\u30ad\u30fc\u5024\u306e\u884c\u306f\u524a\u9664\u3067\u304d\u308b\u306e\u3067\u3001\u89e3\u9664\u3057\u305f\u3044\u89aa\u30ad\u30fc\u5024\u304c\u5916\u90e8\u30ad\u30fc\u3068\u3057\u3066\u4f7f\u7528\u3055\u308c\u3066\u3044\u306a\u3044\u72b6\u614b\u3092\u4f5c\u308b\u3002<br>\u524a\u9664\u3057\u305f\u3044\u89aa\u30ad\u30fc\u5024\u3092\u5916\u90e8\u30ad\u30fc\u3068\u3057\u3066\u3001\u6301\u3064\u884c\u3092\u524a\u9664\u3059\u308c\u3070\u3001\u89aa\u30ad\u30fc\u5024\u3082\u524a\u9664\u3067\u304d\u308b\u3088\u3046\u306b\u306a\u308b\u3002<\/p>\n\n\n\n<p>\u25cfFOREIGN KEY\u5236\u7d04\u306b\u3088\u308b\u95a2\u9023\u4ed8\u3051\u306e\u524a\u9664<br>FOREIGN KEY\u5236\u7d04\u3092\u524a\u9664\u3057\u305f\u308a\u3001\u307e\u305f\u306f\u3001FOREIGN KEY\u5236\u7d04\u3092\u7121\u52b9\u5316\u3057\u305f\u308a\u3059\u308b\u3053\u3068\u3067\u3001\u95a2\u9023\u4ed8\u3051\u3092\u306a\u304f\u305b\u3070\u3001\u89aa\u30ad\u30fc\u3092\u524a\u9664\u3067\u304d\u308b\u3002<\/p>\n\n\n\n<p>\u25cfON DELETE CASCADE\u307e\u305f\u306f\u3001ON DELETE SET NULL\u30aa\u30d7\u30b7\u30e7\u30f3<br>\u5916\u90e8\u30ad\u30fc\u3067\u4f7f\u7528\u3055\u308c\u3066\u3044\u308b\u89aa\u30ad\u30fc\u306f\u30c7\u30d5\u30a9\u30eb\u30c8\u3067\u306f\u3042S\u99c6\u9664\u5236\u9650\u3055\u308c\u3066\u3044\u308b\u305f\u3081\u3001\u524a\u9664\u3067\u304d\u306a\u3044\u3002<br>\u3060\u304c\u3001FOREIGN KEY\u5236\u7d04\u306b\u30aa\u30d7\u30b7\u30e7\u30f3\u3092\u8a2d\u5b9a\u3059\u308b\u3053\u3068\u3067\u3001DELETE\u6587\u304a\u3088\u3073TRUNCATE TABLE \u8868\u540d CASCADE\u6587\u3067\u524a\u9664\u53ef\u80fd\u3068\u6210\u308b\u3002<\/p>\n\n\n\n<p>\u25a0ORDER BY\u53e5<br>ORDER BY\u53e5\u3067\u306f\u3001\u5217\u540d\u3001\u5f0f\u3001\u5217\u5225\u540d\u3001SELECT\u53e5\u306e\u5217\u30ea\u30b9\u30c8\u306e\u9806\u756a\u3092\u6307\u5b9a\u3067\u304d\u308b\u3002<br>ASC(\u6607\u9806)\u3001DESC(\u964d\u9806)\u3001NULLS FIRST\u3001NULLS LAST\u3092\u6307\u5b9a\u3067\u304d\u308b\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"624\" height=\"137\" src=\"https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_10_SQL_12C.png\" alt=\"\" class=\"wp-image-1026\" srcset=\"https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_10_SQL_12C.png 624w, https:\/\/skyit.biz\/wp-content\/uploads\/2021\/01\/12_10_SQL_12C-300x66.png 300w\" sizes=\"auto, (max-width: 624px) 100vw, 624px\" \/><\/figure>\n\n\n\n<p>\u25a0TO_CHAR\u95a2\u6570<br>G(\u6841\u533a\u5207\u308a)\u3001D(\u30d4\u30ea\u30aa\u30c9)\u3092\u4f7f\u3044\u6587\u5b57\u5217\u306b\u5909\u63db\u3067\u304d\u308b\u3002<br>\u4f8b\uff09<br>TO_CHAR(KINGAKU,&#8217;999G999D99&#8242;)<\/p>\n\n\n\n<p>\u25a0TO_TIMESTAMP\u95a2\u6570<br>TIMESTAMP\u578b\u306e\u30c7\u30fc\u30bf\u306f\u3001TO_DATE\u95a2\u6570\u3067\u5909\u63db\u3067\u304d\u306a\u3044\u306e\u3067\u3001\u30a8\u30e9\u30fc\u3068\u6210\u308b\u3002<br>TO_TIMESTAMP\u95a2\u6570\u3092\u4f7f\u3046\u5fc5\u8981\u304c\u3042\u308b\u3002<\/p>\n\n\n\n<p>\u25a0\u526f\u554f\u5408\u305b\u3092\u4f7f\u7528\u3057\u305f\u8868\u306e\u4f5c\u6210\u30ac\u30a4\u30c9\u30e9\u30a4\u30f3<br>\u526f\u554f\u5408\u305b\u3067\u306f\u3001\u30c7\u30fc\u30bf\u578b\u306f\u3001\u6307\u5b9a\u3067\u304d\u306a\u3044\u3002\u5143\u306e\u8868\u304b\u3089\u30b3\u30d4\u30fc\u3055\u308c\u308b\u3002<br>\u5236\u7d04\u3067\u306f\u3001NOT NULL\u5236\u7d04\u306e\u307f\u7d99\u627f\u3055\u308c\u308b\u3002<br>\u526f\u554f\u5408\u305b\u306e\u4e2d\u3067\u3001\u5f0f\u3092\u6307\u5b9a\u3067\u304d\u308b\u3002\u305f\u3060\u3057\u3001\u5217\u540d\u3042\u308b\u3044\u306f\u5217\u5225\u540d\u3092\u6307\u5b9a\u3059\u308b\u5fc5\u8981\u304c\u3042\u308b\u3002<br>\u8868\u306e\u5b9a\u7fa9\u306e\u5217\u6570\u3068\u526f\u554f\u5408\u305b\u306e\u5217\u6570\u306f\u4e00\u81f4\u3055\u305b\u306a\u3051\u308c\u3070\u306a\u3089\u306a\u3044\u3002<\/p>\n\n\n\n<p>\u25a0IN\u6f14\u7b97\u5b50\u3068OR\u6f14\u7b97\u5b50\u306e\u6bd4\u8f03<br>IN\u6f14\u7b97\u5b50\u3068OR\u6f14\u7b97\u5b50\u306f\u3001\u51e6\u7406\u901f\u5ea6\u306f\u3001\u540c\u3058\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3068\u306a\u308b\u3002<br>IN\u6f14\u7b97\u5b50\u3092\u4f7f\u7528\u3059\u308b\u30e1\u30ea\u30c3\u30c8\u306f\u3001\u6761\u4ef6\u5f0f\u306e\u8ad6\u7406\u6027\u3001\u308f\u304b\u308a\u3084\u3059\u3055\u306e\u5411\u4e0a\u306b\u3042\u308b\u3002<\/p>\n\n\n\n<p>\u25a0GROUP BY\u53e5\u3068\u4ed6\u306e\u53e5\uff08SELECT\u53e5\u3001ORDER BY\u53e5\uff09\u3068\u306e\u6307\u5b9a\u9805\u76ee\u306e\u4e00\u81f4<br>SELECT\u53e5\u3068GROUP BY\u53e5\u3002GROUP BY\u53e5\u3068ORDER BY\u53e5\u306b\u306f\u3001\u540c\u3058\u3082\u306e\u3092\u6307\u5b9a\u3059\u308b\u5fc5\u8981\u304c\u3042\u308b\u3002<\/p>\n\n\n\n<p>\u25a0SQL * Plus\u304a\u3088\u3073SQL Developer\u306e\u6a5f\u80fd\u3067\u3042\u308b\u7f6e\u63db\u5909\u6570\u306b\u3064\u3044\u3066<br>\u7f6e\u63db\u5909\u6570\u306f\u3001\uff06\u30b7\u30f3\u30b0\u30eb\u30a2\u30f3\u30d1\u30b5\u30f3\u30c9\u3001\uff06\uff06\u30c0\u30d6\u30eb\u30a2\u30f3\u30d1\u30b5\u30f3\u30c9\u306e2\u7a2e\u985e\u304c\u3042\u308b\u3002<\/p>\n\n\n\n<p>\u521d\u56de\u3060\u3051\u5165\u529b\u306f\u3001&amp;&amp;\u3092\u4f7f\u3046\u3002<\/p>\n\n\n\n<p>\u25a0\u30ea\u30ec\u30fc\u30b7\u30e7\u30ca\u30eb\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u7ba1\u7406\u30b7\u30b9\u30c6\u30e0\u306b\u3064\u3044\u3066<br>\u30ea\u30ec\u30fc\u30b7\u30e7\u30ca\u30eb\u30fb\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9(RDB)\u306b\u306f\u6b21\u306e\u3088\u3046\u306a\u7279\u5fb4\u304c\u3042\u308a\u307e\u3059\u3002<br>\u30fb\u30c7\u30fc\u30bf\u3092\u884c\u3068\u5217\u304b\u3089\u306a\u308b2\u6b21\u5143\u306e\u8868\u5f62\u5f0f\u3067\u683c\u7d0d\u3059\u308b<br>\u30fb\u95a2\u9023\u306e\u3042\u308b\u30c7\u30fc\u30bf\u3092\u30b0\u30eb\u30fc\u30d7\u5316\u3057\u3001\u8907\u6570\u306e\u8868\u306b\u5206\u5272\u3057\u3066\u7ba1\u7406\u3059\u308b<br>\u30fb\u95a2\u9023\u306e\u3042\u308b\u8868\u540c\u58eb\u3092\u8868\u306b\u683c\u7d0d\u3055\u308c\u305f\u30c7\u30fc\u30bf\u306b\u57fa\u3065\u3044\u3066\u95a2\u9023\u4ed8\u3051\u308b\u3053\u3068\u304c\u3067\u304d\u308b<br>\u30fbE. F. Codd\u306e\u30eb\u30fc\u30eb(\u30a8\u30c9\u30ac\u30fc\u30fbF\u30fb\u30b3\u30c3\u30c9\u306b\u3088\u3063\u3066\u8003\u6848\u3055\u308c\u305fRDBMS\u306b\u95a2\u3059\u308b\u898f\u5247)\u3092\u30b5\u30dd\u30fc\u30c8\u3059\u308b<br>\u30fbSQL\u3092\u4f7f\u7528\u3057\u3066\u30c7\u30fc\u30bf\u306b\u30a2\u30af\u30bb\u30b9\u3059\u308b<\/p>\n\n\n\n<p>\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u30fb\u30ea\u30ec\u30fc\u30b7\u30e7\u30ca\u30eb\u578b\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306f\u3001\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u6307\u5411\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9(OODB)\u3068\u3082\u547c\u3073\u307e\u3059\u3002\u6b21\u306e\u7279\u5fb4\u304c\u3042\u308a\u307e\u3059\u3002<br>\u30fb\u30ea\u30ec\u30fc\u30b7\u30e7\u30ca\u30eb\u578b\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306e\u6a5f\u80fd\u3092\u62e1\u5f35\u3057\u3001\u5b8c\u5168\u306a\u4e92\u63db\u6027\u3092\u6301\u3064<br>\u30fb\u30c7\u30fc\u30bf\u69cb\u9020\u304c\u5b9a\u7fa9\u3055\u308c\u305f\u30e1\u30bd\u30c3\u30c9\u304c\u7d44\u307f\u8fbc\u307e\u308c\u3066\u3044\u308b<br>\u30fb\u540c\u3058\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u3067\u8907\u6570\u306e\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u30b5\u30dd\u30fc\u30c8\u3059\u308b<\/p>\n\n\n\n<p>[\u7b2c1\u6b63\u898f\u5f62(1NF)]<br>\u7b2c1\u6b63\u898f\u5316\u306f\u3001\u975e\u6b63\u898f\u5f62\u306e\u8868\u306b\u6b21\u306e\u4f5c\u696d\u3092\u884c\u3044\u307e\u3059\u3002<br>\u30fb\u4e3b\u30ad\u30fc\u3092\u8a2d\u5b9a\u3059\u308b<br>\u30fb\u7e70\u308a\u8fd4\u3057\u73fe\u308c\u308b\u5217\u306e\u30c7\u30fc\u30bf\u3092\u30b0\u30eb\u30fc\u30d7\u5316\u3057\u3066\u3001\u5225\u306e\u8868\u306b\u5207\u308a\u96e2\u3059<br>\u30fb\u5c0e\u51fa\u9805\u76ee(\u4ed6\u306e\u5c5e\u6027\u304b\u3089\u7b97\u51fa\u3067\u304d\u308b\u9805\u76ee)\u3092\u524a\u9664\u3059\u308b<\/p>\n\n\n\n<p>\u30fb\u7b2c2\u6b63\u898f\u5f62<br>\u7b2c2\u6b63\u898f\u5316\u306f\u3001\u7b2c1\u6b63\u898f\u5f62\u306e\u8868\u304b\u3089\u90e8\u5206\u95a2\u6570\u5f93\u5c5e\u6027\u3067\u3042\u308b\u3082\u306e\u3092\u9664\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u30fb\u7b2c3\u6b63\u898f\u5f62<br>\u7b2c3\u6b63\u898f\u5316\u306f\u3001\u7b2c2\u6b63\u898f\u5f62\u304b\u3089\u63a8\u79fb\u95a2\u6570\u5f93\u5c5e\u6027\u3092\u9664\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u3010\u6b63\u898f\u5316\u3011<br>\u6b63\u898f\u5316\u3068\u306f\u3001\u30c7\u30fc\u30bf\u306e\u91cd\u8907\u3092\u6392\u9664\u3057\u3001\u30c7\u30fc\u30bf\u9593\u306e\u6b63\u3057\u3044\u30ea\u30ec\u30fc\u30b7\u30e7\u30f3\u30b7\u30c3\u30d7\u3092\u8a2d\u5b9a\u3057\u3066\u30c7\u30fc\u30bf\u3092\u4e00\u5143\u7ba1\u7406\u3067\u304d\u308b\u3088\u3046\u306b\u3059\u308b\u3053\u3068\u3067\u3059\u3002\u6b63\u898f\u5316\u306f\u30ea\u30ec\u30fc\u30b7\u30e7\u30ca\u30eb\u30fb\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306e\u8a2d\u8a08\u306b\u304a\u3044\u3066\u91cd\u8981\u306a\u4f5c\u696d\u3067\u3059\u3002<br>\u6b63\u898f\u5316\u306b\u306f\u7b2c1\u6b63\u898f\u5316\u304b\u3089\u7b2c5\u6b63\u898f\u5316\u304c\u3042\u308a\u307e\u3059\u304c\u3001\u307b\u3068\u3093\u3069\u306e\u5834\u5408\u306f\u7b2c3\u6b63\u898f\u5316\u307e\u3067\u884c\u3048\u3070\u3001\u5b9f\u52d9\u4e0a\u306f\u554f\u984c\u306a\u3044\u3068\u3055\u308c\u3066\u3044\u307e\u3059\u3002<br>\u6b63\u898f\u5316\u3055\u308c\u305f\u3082\u306e\u3092\u6b63\u898f\u5f62\u3068\u3044\u3044\u307e\u3059\u3002\u3053\u3053\u3067\u306f\u7b2c3\u6b63\u898f\u5f62\u307e\u3067\u306e\u6b63\u898f\u5316\u3092\u89e3\u8aac\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<p>[\u975e\u6b63\u898f\u5f62]<br>\u975e\u6b63\u898f\u5f62\u306f\u6b63\u898f\u5316\u3055\u308c\u3066\u3044\u306a\u3044\u30c7\u30fc\u30bf\u3067\u3059\u3002<br>\u4f8b\u3048\u3070\u3001\u4ee5\u4e0b\u306e\u53d7\u6ce8\u4f1d\u7968\u306e\u3088\u3046\u306a\u30c7\u30fc\u30bf\u306f\u975e\u6b63\u898f\u5f62\u3067\u3059\u3002\u3053\u306e\u53d7\u6ce8\u4f1d\u7968\u3092\u6b63\u898f\u5316\u3057\u3066\u3044\u304d\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n<p>[\u7b2c2\u6b63\u898f\u5f62(2NF)]<br>\u7b2c2\u6b63\u898f\u5316\u306f\u3001\u7b2c1\u6b63\u898f\u5f62\u306e\u8868\u304b\u3089\u90e8\u5206\u95a2\u6570\u5f93\u5c5e\u6027\u3067\u3042\u308b\u3082\u306e\u3092\u9664\u304d\u307e\u3059\u3002<br>\u307e\u305a\u3001\u95a2\u6570\u5f93\u5c5e\u6027\u3068\u306f\u300c\u3042\u308b\u5c5e\u6027(\u5217)\u306e\u5024X\u304c\u6c7a\u307e\u308b\u3068\u3001\u5225\u306e\u5c5e\u6027\u306e\u5024Y\u304c\u81ea\u52d5\u7684\u306b\u6c7a\u307e\u308b\u300d\u3053\u3068\u3067\u3059\u3002\u3053\u306e\u5834\u5408\u300cX \u2192 Y\u300d\u3068\u8868\u8a18\u3057\u3001Y\u306fX\u306b\u95a2\u6570\u5f93\u5c5e\u3059\u308b\u3068\u3044\u3044\u307e\u3059\u3002<br>\u90e8\u5206\u95a2\u6570\u5f93\u5c5e\u6027\u306f\u3001Y\u304cX\u306e\u4e00\u90e8\u306b\u95a2\u6570\u5f93\u5c5e\u3059\u308b\u3053\u3068\u3067\u3059\u3002\u7b2c2\u6b63\u898f\u5316\u306f\u3001\u3053\u306e\u90e8\u5206\u95a2\u6570\u5f93\u5c5e\u6027\u3092\u9664\u304d\u3001\u4e3b\u30ad\u30fc\u5217\u306e\u5024\u304c\u6c7a\u307e\u308c\u3070\u4e3b\u30ad\u30fc\u4ee5\u5916\u306e\u5217\u306e\u5024\u304c\u6c7a\u307e\u308b\u3088\u3046\u306a\u8868\u306b\u5206\u5272\u3057\u307e\u3059\u3002\u3064\u307e\u308a\u3001\u8907\u5408\u4e3b\u30ad\u30fc\u306e\u4e00\u90e8\u306e\u5217\u306e\u5024\u304b\u3089\u5c0e\u304d\u51fa\u305b\u308b\u5217\u304c\u3042\u308c\u3070\u3001\u305d\u308c\u3089\u3092\u5225\u306e\u8868\u306b\u5206\u5272\u3059\u308b\u3068\u3044\u3046\u3053\u3068\u3067\u3059\u3002<\/p>\n\n\n\n<p>[\u7b2c3\u6b63\u898f\u5f62(3NF)]<br>\u7b2c3\u6b63\u898f\u5316\u306f\u3001\u7b2c2\u6b63\u898f\u5f62\u304b\u3089\u63a8\u79fb\u95a2\u6570\u5f93\u5c5e\u6027\u3092\u9664\u304d\u307e\u3059\u3002<br>\u63a8\u79fb\u95a2\u6570\u5f93\u5c5e\u6027\u3068\u306f\u3001\u300cX\u304c\u6c7a\u307e\u308b\u3068Y\u304c\u6c7a\u307e\u308a\u3001Y\u304c\u6c7a\u307e\u308b\u3068Z\u304c\u6c7a\u307e\u308b\u300d\u3068\u3044\u3046\u95a2\u4fc2\u3067\u3059\u3002<br>X \u2192 Y\u3001 Y \u2192 Z\u3001\u4f46\u3057Y \u2192 X\u306f\u4e0d\u6210\u7acb\u306e\u5834\u5408\u3001\u300cX \u2192 Z\u300d\u3068\u8868\u8a18\u3057\u3001Z\u306fX\u306b\u63a8\u79fb\u95a2\u6570\u5f93\u5c5e\u3067\u3042\u308b\u3068\u3044\u3044\u307e\u3059\u3002<br>\u4e0a\u8a18\u306e\u6761\u4ef6\u306e\u8868\u8a18\u306f\u3001\u305d\u308c\u305e\u308c<br>\u3000X \u2192 Y : \u4e3b\u30ad\u30fc\u3068\u3001\u4e3b\u30ad\u30fc\u4ee5\u5916\u306e\u5217(\u975e\u30ad\u30fc\u5c5e\u6027)\u306e\u95a2\u6570\u5f93\u5c5e\u6027<br>\u3000Y \u2192 Z : \u975e\u30ad\u30fc\u5c5e\u6027\u9593\u306e\u95a2\u6570\u5f93\u5c5e\u6027<br>\u3092\u8868\u3057\u3066\u3044\u307e\u3059\u3002<br>\u300cX \u2192 Y\u300d\u306e\u90e8\u5206\u306f\u3001\u7b2c2\u6b63\u898f\u5316\u3067\u5b8c\u5168\u95a2\u6570\u5f93\u5c5e\u6027\u307e\u3067\u6574\u7406\u3057\u3066\u3044\u308b\u306e\u3067\u3001\u3053\u306e\u90e8\u5206\u306e\u4f5c\u696d\u306f\u4e0d\u8981\u3067\u3059\u3002\u6b8b\u308b\u975e\u30ad\u30fc\u5c5e\u6027\u9593\u306e\u95a2\u6570\u5f93\u5c5e\u6027\u300cY \u2192 Z\u300d\u3092\u9664\u304f\u4f5c\u696d\u304c\u3001\u7b2c3\u6b63\u898f\u5316\u306e\u63a8\u79fb\u95a2\u6570\u5f93\u5c5e\u6027\u3092\u9664\u304f\u3068\u3044\u3046\u3053\u3068\u306b\u306a\u308a\u307e\u3059\u3002\u3064\u307e\u308a\u3001\u4e3b\u30ad\u30fc\u4ee5\u5916\u306e\u5217\u304c\u76f8\u4e92\u306b\u4f9d\u5b58\u95a2\u4fc2\u3092\u6301\u305f\u306a\u3044\u3088\u3046\u306b\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<p>SELECT\u6587\u306e\u691c\u7d22\u7d50\u679c\u304b\u3089\u91cd\u8907\u3057\u305f\u884c\u3092\u6392\u9664\u3059\u308b\u306b\u306f\u3001SELECT\u30ad\u30fc\u30ef\u30fc\u30c9\u306e\u76f4\u5f8c\u306b1\u5ea6\u3060\u3051DISTINCT\u30ad\u30fc\u30ef\u30fc\u30c9\u3092\u6307\u5b9a\u3057\u307e\u3059\u3002<br>DISTINCT\u30ad\u30fc\u30ef\u30fc\u30c9\u306b\u7d9a\u3051\u3066\u8907\u6570\u306e\u9805\u76ee\u3092\u6307\u5b9a\u3057\u305f\u5834\u5408\u306f\u3001\u6307\u5b9a\u3057\u305f\u9805\u76ee\u306e\u7d44\u5408\u305b\u3067\u91cd\u8907\u3092\u6392\u9664\u3057\u305f\u884c\u304c\u8868\u793a\u3055\u308c\u307e\u3059\u3002<br>\u30fbSELECT DISTINCT(*) FROM sales;<br>\u30fbSELECT DISTINCT (prod_id, cust_id) FROM sales;<br>DISTINCT\u30ad\u30fc\u30ef\u30fc\u30c9\u306e\u5f8c\u306e\u9805\u76ee\u3092()\u62ec\u5f27\u3067\u56f2\u3080\u3068\u30a8\u30e9\u30fc\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u9664\u7b97\u3068\u4e57\u7b97\u306e\u512a\u5148\u9806\u4f4d\u306f\u540c\u3058\u3067\u3059\u3002\u540c\u3058\u512a\u5148\u9806\u4f4d\u306e\u6f14\u7b97\u5b50\u304c\u8907\u6570\u4f7f\u308f\u308c\u3066\u3044\u308b\u5834\u5408\u306f\u3001\u5de6\u5074\u306e\u8a08\u7b97\u304b\u3089\u9806\u756a\u306b\u884c\u308f\u308c\u307e\u3059\u3002<\/p>\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u25a0\u30c7\u30ab\u30eb\u30c8\u7a4d\u25bc\u7d50\u5408\u6761\u4ef6\u304c\u6307\u5b9a\u3055\u308c\u3066\u3044\u306a\u3044\u30c7\u30ab\u30eb\u30c8\u7a4d(Oracle\u7d50\u5408\u69cb\u6587)SELECT * FROM EMP, DEPT; \u25bcCROSS JOIN\u53e5\u306b\u3088\u308b\u30af\u30ed\u30b9\u7d50\u5408SELECT * FROM EMP CROSS JOIN [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":1025,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[38,52,12],"tags":[],"class_list":{"0":"post-1016","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-bronze-dba-12c","8":"category-bronze-sql-12c","9":"category-oracle"},"_links":{"self":[{"href":"https:\/\/skyit.biz\/index.php?rest_route=\/wp\/v2\/posts\/1016","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/skyit.biz\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/skyit.biz\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/skyit.biz\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/skyit.biz\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1016"}],"version-history":[{"count":1,"href":"https:\/\/skyit.biz\/index.php?rest_route=\/wp\/v2\/posts\/1016\/revisions"}],"predecessor-version":[{"id":1027,"href":"https:\/\/skyit.biz\/index.php?rest_route=\/wp\/v2\/posts\/1016\/revisions\/1027"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/skyit.biz\/index.php?rest_route=\/wp\/v2\/media\/1025"}],"wp:attachment":[{"href":"https:\/\/skyit.biz\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1016"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/skyit.biz\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1016"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/skyit.biz\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1016"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}