{"id":6648,"date":"2024-02-02T15:45:20","date_gmt":"2024-02-02T06:45:20","guid":{"rendered":"https:\/\/techmania.jp\/blog\/?p=6648"},"modified":"2024-02-05T11:30:50","modified_gmt":"2024-02-05T02:30:50","slug":"sql-null","status":"publish","type":"post","link":"https:\/\/techmania.jp\/blog\/sql-null\/","title":{"rendered":"\u3010SQL\u3011NULL\u306e\u6271\u3044\u65b9\u3092\u30b5\u30f3\u30d7\u30eb\u30b3\u30fc\u30c9\u3067\u5206\u304b\u308a\u3084\u3059\u304f\u89e3\u8aac"},"content":{"rendered":"

NULL\u306e\u5224\u5b9a\u306b\u306f\u300cIS NULL\u300d\u3084\u300cIS NOT NULL\u300d\u3092\u4f7f\u7528\u3057\u307e\u3059\u304c\u3001\u305d\u306e\u6271\u3044\u306b\u306f\u6ce8\u610f\u304c\u5fc5\u8981\u3067\u3059\u3002\u672c\u8a18\u4e8b\u3067\u306f\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306b\u304a\u3051\u308b\u300cNULL\u300d\u5024\u306b\u3064\u3044\u3066\u89e3\u8aac\u3057\u307e\u3059\u3002\u305c\u3072\u4eca\u5f8c\u306eSQL\u5b66\u7fd2\u306e\u53c2\u8003\u306b\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n\n\n

\u305d\u3082\u305d\u3082\u300cNULL\u300d\u3068\u306f\uff1f<\/h2>\n\n\n

NULL\u5024\u3068\u306f\u3001\u5024\u3068\u8a00\u3063\u3066\u3044\u307e\u3059\u304c\u3001\u308f\u304b\u308a\u3084\u3059\u304f\u8a00\u3046\u3068\u3001\u300c\u30c7\u30fc\u30bf\u304c\u5b58\u5728\u3057\u306a\u3044\u300d\u3068\u3044\u3046\u6982\u5ff5\u3067\u3059\u3002\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306b\u304a\u3044\u3066\u306f\u3001\u30d5\u30a3\u30fc\u30eb\u30c9\u306b\u5024\u304c\u5165\u529b\u3055\u308c\u3066\u3044\u306a\u3044\u5834\u5408\u306b\u300c\u5024\u304cNULL\u3067\u3042\u308b\u300d\u3068\u3044\u3044\u307e\u3059\u3002NULL\u5024\u306f\u3001\u30bc\u30ed\u5024\u3084\u7a7a\u6587\u5b57\u3068\u306f\u7570\u306a\u308a\u307e\u3059\u3002<\/span><\/span><\/p>\n\n\n

\n

\u3042\u306a\u305f\u306e\u3054\u5e0c\u671b\u306b\u6cbf\u3063\u305f\u6848\u4ef6\u304c\u5fc5\u305a<\/span>\u898b\u3064\u304b\u308a\u307e\u3059
\u3010\u30d5\u30ea\u30fc\u30e9\u30f3\u30b9\u5411\u3051\u3011\u9ad8\u53ce\u5165<\/span>\u30fb<\/span>\u597d\u5f85\u9047<\/span>\u306e\u6848\u4ef6\u3092\u3054\u7d39\u4ecb<\/span><\/p><\/a>\n<\/div>\n\n

\"TECH<\/a>\n<\/div>\n\n
\n

\u226b\u307e\u305a\u306f\u7c21\u535860<\/span>\u79d2\u3067\u7121\u6599\u304a\u554f\u3044\u5408\u308f\u305b<\/span>\u304b\u3089\u226a<\/p><\/a>\n<\/div>\n\n\n\n

\u30b5\u30f3\u30d7\u30eb\u30b3\u30fc\u30c9<\/h2>\n\n\n

\u8aac\u660e\u306b\u306f\u3001\u30b5\u30f3\u30d7\u30eb\u3068\u3057\u3066\u300ctest\u300d\u30c6\u30fc\u30d6\u30eb\u3092\u7528\u610f\u3057\u307e\u3057\u305f\u3002<\/p>\n

\u300ctest\u300d\u30c6\u30fc\u30d6\u30eb<\/strong><\/p>\n\n\n

ID\uff08id\uff09<\/strong><\/td>\u6c0f\u540d\uff08name\uff09<\/strong><\/td>\u70b9\u6570\uff08point\uff09<\/strong><\/td><\/tr>
1<\/td>\u79cb\u5c71<\/td>80<\/td><\/tr>
2<\/td>\u4e45\u4fdd\u7530<\/td>100<\/td><\/tr>
3<\/td>\u4f50\u3005\u6728<\/td>NULL<\/td><\/tr>
4<\/td>\u4f50\u85e4<\/td>70<\/td><\/tr>
5<\/td>\u9234\u6728<\/td>NULL<\/td><\/tr>
6<\/td>\u7530\u4e2d<\/td>90<\/td><\/tr>
7<\/td>\u571f\u5c4b<\/td>60<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

IS NULL\u6f14\u7b97\u5b50<\/h2>\n\n\n

NULL\u5224\u5b9a\u3092\u884c\u3046\u6f14\u7b97\u5b50\u3067\u3001\u4e3b\u306b\u300cWHERE\u300d\u5185\u3067\u4f7f\u7528\u3055\u308c\u307e\u3059\u3002\u5927\u534a\u306e\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u3067\u4f7f\u3048\u308b\u6f14\u7b97\u5b50\u3067\u3059\u3002<\/p>\n\n\n

\u300cIS NULL\u300d\u6f14\u7b97\u5b50\u3067NULL\u3092\u62bd\u51fa\u3059\u308b<\/h3>\n\n\n

\u300cIS NULL\u300d\u6f14\u7b97\u5b50\u3092\u7528\u3044\u3066NULL\u5024\u3092\u62bd\u51fa\u3067\u304d\u307e\u3059\u3002<\/p>\n

\u3010\u4f7f\u7528\u30a4\u30e1\u30fc\u30b8\u3011<\/strong><\/p>\n\n\n

SELECT \u30ab\u30e9\u30e0\u540d FROM \u30c6\u30fc\u30d6\u30eb\u540d WHERE \u30ab\u30e9\u30e0\u540d IS NULL;<\/code><\/pre>\n\n\n
\u30c6\u30b9\u30c8\u3092\u53d7\u3051\u3066\u3044\u306a\u3044\u751f\u5f92\u3092\u62bd\u51fa\u3057\u307e\u3059\u3002<\/p>\n
\u3010SQL\u5b9f\u884c\u30b3\u30fc\u30c9\u3011<\/strong><\/p>\n\n\n
SELECT * FROM test WHERE point IS NULL;<\/code><\/pre>\n\n\n
\u3010\u5b9f\u884c\u7d50\u679c\u3011<\/strong><\/p>\n\n\n
id<\/strong><\/td>name<\/strong><\/td>point<\/strong><\/td><\/tr>
3<\/td>\u4f50\u3005\u6728<\/td>NULL<\/td><\/tr>
5<\/td>\u9234\u6728<\/td>NULL<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
\u300cIS NOT NULL\u300d\u6f14\u7b97\u5b50\u3067NULL\u4ee5\u5916\u3092\u62bd\u51fa\u3059\u308b<\/h3>\n\n\n
\u300cIS NOT NULL\u300d\u6f14\u7b97\u5b50\u3092\u7528\u3044\u3066NULL\u5024\u4ee5\u5916\u3092\u62bd\u51fa\u3067\u304d\u307e\u3059\u3002<\/p>\n
\u3010\u4f7f\u7528\u30a4\u30e1\u30fc\u30b8\u3011<\/strong><\/p>\n\n\n
SELECT \u30ab\u30e9\u30e0\u540d FROM \u30c6\u30fc\u30d6\u30eb\u540d WHERE \u30ab\u30e9\u30e0\u540d IS NOT NULL;<\/code><\/pre>\n\n\n
\u30c6\u30b9\u30c8\u3092\u53d7\u3051\u305f\u751f\u5f92\u3092\u62bd\u51fa\u3057\u307e\u3059\u3002<\/p>\n
\u3010SQL\u5b9f\u884c\u30b3\u30fc\u30c9\u3011<\/strong><\/p>\n\n\n
SELECT * FROM test WHERE point IS NULL;<\/code><\/pre>\n\n\n
\u3010\u5b9f\u884c\u7d50\u679c\u3011<\/strong><\/p>\n\n\n
id<\/strong><\/td>name<\/strong><\/td>point<\/strong><\/td><\/tr>
1<\/td>\u79cb\u5c71<\/td>80<\/td><\/tr>
2<\/td>\u4e45\u4fdd\u7530<\/td>100<\/td><\/tr>
4<\/td>\u4f50\u85e4<\/td>70<\/td><\/tr>
6<\/td>\u7530\u4e2d<\/td>90<\/td><\/tr>
7<\/td>\u571f\u5c4b<\/td>60<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
NULL\u306f\u7b49\u53f7\u30fb\u7b49\u53f7\u5426\u5b9a\u30fb\u4e0d\u7b49\u53f7\u306e\u5bfe\u8c61\u306b\u306a\u3089\u306a\u3044<\/h3>\n\n\n
\u30c7\u30fc\u30bf\u3092\u62bd\u51fa\u3059\u308b\u969b\u3001\u300c\u30ab\u30e9\u30e0\u540d != \u2018\u691c\u7d22\u5024\u2019\u300d\u3068\u3057\u3066\u3082NULL\u5024\u3092\u542b\u3080\u30ec\u30b3\u30fc\u30c9\u306f\u62bd\u51fa\u3055\u308c\u307e\u305b\u3093\u3002\u307e\u305f\u3001\u300c\u30ab\u30e9\u30e0\u540d = NULL\u300d\u3067\u306fNULL\u3092\u542b\u3080\u30c7\u30fc\u30bf\u3092\u62bd\u51fa\u3067\u304d\u307e\u305b\u3093\u3002\u3053\u308c\u306f\u3001NULL\u306f\u7b49\u53f7\uff08=\uff09\u3001\u7b49\u53f7\u5426\u5b9a\uff08!=\uff09\u3001\u4e0d\u7b49\u53f7\uff08<\u3001>\u3001\u2266\u3001\u2267\uff09\u306e\u5bfe\u8c61\u306b\u306a\u3089\u306a\u3044\u304b\u3089\u3067\u3059\u3002\u5b9f\u969b\u306b\u898b\u3066\u307f\u307e\u3057\u3087\u3046\u3002<\/p>\n
\u25c6\u7b49\u53f7\u306f\u4f7f\u3048\u306a\u3044<\/strong><\/p>\n
\u3010SQL\u5b9f\u884c\u30b3\u30fc\u30c9\u3011<\/strong><\/p>\n\n\n
SELECT * FROM test WHERE point = NULL;<\/code><\/pre>\n\n\n
\u3010\u5b9f\u884c\u7d50\u679c\u3011<\/strong><\/p>\n
\uff08NULL\u3092\u542b\u3080\u30ec\u30b3\u30fc\u30c9\u3082\u62bd\u51fa\u3067\u304d\u306a\u3044\uff09<\/p>\n
\u62bd\u51fa\u30c7\u30fc\u30bf\u306a\u3057<\/p>\n
\u25c6\u7b49\u53f7\u5426\u5b9a\u306f\u4f7f\u3048\u306a\u3044\u2460<\/strong><\/p>\n
\u3010SQL\u5b9f\u884c\u30b3\u30fc\u30c9\u3011<\/strong><\/p>\n\n\n
SELECT * FROM test WHERE point != NULL;<\/code><\/pre>\n\n\n
\u3010\u5b9f\u884c\u7d50\u679c\u3011<\/strong><\/p>\n
\uff08NULL\u3092\u542b\u3080\u30ec\u30b3\u30fc\u30c9\u3082\u62bd\u51fa\u3055\u308c\u3066\u3057\u307e\u3046\uff09<\/p>\n\n\n
id<\/strong><\/td>name<\/strong><\/td>point<\/strong><\/td><\/tr>
1<\/td>\u79cb\u5c71<\/td>80<\/td><\/tr>
2<\/td>\u4e45\u4fdd\u7530<\/td>100<\/td><\/tr>
3<\/td>\u4f50\u3005\u6728<\/td>NULL<\/td><\/tr>
4<\/td>\u4f50\u85e4<\/td>70<\/td><\/tr>
5<\/td>\u9234\u6728<\/td>NULL<\/td><\/tr>
6<\/td>\u7530\u4e2d<\/td>90<\/td><\/tr>
7<\/td>\u571f\u5c4b<\/td>60<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n
\u25c6\u7b49\u53f7\u5426\u5b9a\u306f\u4f7f\u3048\u306a\u3044\u2461<\/strong><\/p>\n
\u3010SQL\u5b9f\u884c\u30b3\u30fc\u30c9\u3011<\/strong><\/p>\n\n\n
SELECT * FROM test WHERE point != 80;<\/code><\/pre>\n\n\n
\u3010\u5b9f\u884c\u7d50\u679c\u3011<\/strong><\/p>\n
\uff08NULL\u3092\u542b\u3080\u30ec\u30b3\u30fc\u30c9\u304c\u62bd\u51fa\u3067\u304d\u306a\u3044\uff09<\/p>\n\n\n
id<\/strong><\/td>name<\/strong><\/td>point<\/strong><\/td><\/tr>
2<\/td>\u4e45\u4fdd\u7530<\/td>100<\/td><\/tr>
4<\/td>\u4f50\u85e4<\/td>70<\/td><\/tr>
6<\/td>\u7530\u4e2d<\/td>90<\/td><\/tr>
7<\/td>\u571f\u5c4b<\/td>60<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n
\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u3067NULL\u3092\u691c\u7d22\u3059\u308b\u306b\u306f\u3001\u300cIS NULL\u300d\u6f14\u7b97\u5b50\u3092\u3001NULL\u3092\u542b\u307e\u306a\u3044\u30ec\u30b3\u30fc\u30c9\u3092\u691c\u7d22\u3059\u308b\u306b\u306f\u300cIS NOT NULL\u300d\u6f14\u7b97\u5b50\u3092\u4f7f\u7528\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n
NULL\u3068\u7a7a\u6587\u5b57\u306e\u9055\u3044<\/h3>\n\n\n
\u5192\u982d\u3067\u3082\u8aac\u660e\u3057\u305f\u901a\u308a\u3001NULL\u3068\u7a7a\u6587\u5b57\u306f\u5225\u7269\u3067\u3059\u3002<\/p>\n
NULL\u304c\u300c\u4e2d\u8eab\u304c\u5b58\u5728\u3057\u306a\u3044\u300d\u306e\u306b\u5bfe\u3057\u3001\u7a7a\u6587\u5b57\u306f\u300c\u9577\u30550\u306e\u6587\u5b57\u5217\u3001\u3059\u306a\u308f\u3061\u3001\u7a7a\u306e\u30c7\u30fc\u30bf\u304c\u5b58\u5728\u3059\u308b\u300d\u3068\u8868\u73fe\u3057\u307e\u3059\u3002
<\/span><\/p>\n\n\n
\u7a7a\u6587\u5b57\u306e\u307f\u62bd\u51fa\u3059\u308b<\/h4>\n\n\n\n
SELECT * FROM \u30c6\u30fc\u30d6\u30eb\u540d WHERE \u30ab\u30e9\u30e0\u540d = '';<\/code><\/pre>\n\n\n\n
NULL\u306e\u307f\u62bd\u51fa\u3059\u308b<\/h4>\n\n\n\n
SELECT * FROM \u30c6\u30fc\u30d6\u30eb\u540d WHERE \u30ab\u30e9\u30e0\u540d IS NULL;<\/code><\/pre>\n\n\n\n
\u7a7a\u6587\u5b57\u3068NULL\u5024\u4ee5\u5916\u3092\u62bd\u51fa\u3059\u308b(str != ”;\u306e\u6319\u52d5\u306b\u6ce8\u610f)<\/h4>\n\n\n\n
SELECT * FROM \u30c6\u30fc\u30d6\u30eb\u540d WHERE \u30ab\u30e9\u30e0\u540d != '';<\/code><\/pre>\n\n\n\n
NULL\u5024\u4ee5\u5916\u3092\u62bd\u51fa\u3059\u308b<\/h4>\n\n\n\n
SELECT * FROM \u30c6\u30fc\u30d6\u30eb\u540d WHERE \u30ab\u30e9\u30e0\u540d IS NOT NULL;<\/code><\/pre>\n\n\n\n
\u300cISNULL\u300d\u95a2\u6570<\/h2>\n\n\n
\u300cISNULL\u300d\u95a2\u6570\u306fNULL\u3092\u4efb\u610f\u306e\u6587\u5b57\u5217\u306b\u7f6e\u63db\u3059\u308b\u95a2\u6570\u3067\u3059\u3002SQL Server\u30fbAccess\u3067\u4f7f\u7528\u3067\u304d\u307e\u3059\u3002\u307b\u304b\u306e\u4e3b\u8981\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u3067\u306f\u540c\u3058\u6a5f\u80fd\u3092\u6301\u3064\u95a2\u6570\u540d\u304c\u3042\u308b\u306e\u3067\u4f75\u305b\u3066\u7d39\u4ecb\u3057\u307e\u3059\u3002<\/p>\n
\u3010\u4f7f\u7528\u30a4\u30e1\u30fc\u30b8\u3011<\/strong><\/p>\n\n\n
ISNULL([\u6307\u5b9a\u3059\u308b\u30ab\u30e9\u30e0], [\u7f6e\u63db\u3057\u305f\u3044\u6587\u5b57\u5217])<\/code><\/pre>\n\n\n
\u7b2c\u4e00\u5f15\u6570\u306b\u300cNULL\u3092\u30c1\u30a7\u30c3\u30af\u3059\u308b\u30ab\u30e9\u30e0\u540d\u300d\u3001\u7b2c\u4e8c\u5f15\u6570\u306b\u300cNULL\u3060\u3063\u305f\u5834\u5408\u306b\u7f6e\u63db\u3059\u308b\u6587\u5b57\u5217\u300d\u3092\u5165\u529b\u3057\u307e\u3059\u3002<\/p>\n
\u30c6\u30b9\u30c8\u30c6\u30fc\u30d6\u30eb\u306e\u70b9\u6570\u304cNULL\u306e\u5834\u5408\u306b\u300c\u672a\u53d7\u9a13\u300d\u306b\u8868\u793a\u3057\u305f\u3044\u5834\u5408\u306f\u6b21\u306e\u3088\u3046\u306b\u8a18\u8ff0\u3057\u307e\u3059\u3002<\/p>\n
\u3010SQL\u5b9f\u884c\u30b3\u30fc\u30c9\u3011<\/strong><\/p>\n\n\n
SELECT ISNULL(point,'\u672a\u53d7\u9a13') FROM test;<\/code><\/pre>\n\n\n\n
\u74b0\u5883\u3054\u3068\u306e\u985e\u4f3c\u95a2\u6570<\/h3>\n\n\n
\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306b\u3088\u3063\u3066\u985e\u4f3c\u95a2\u6570\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n
\u25c6Mysql\u30fbSQLite<\/strong><\/p>\n\n\n
SELECT IFNULL(point,'\u672a\u53d7\u9a13') FROM test;<\/code><\/pre>\n\n\n
\u25c6PostgreSQL<\/strong><\/p>\n\n\n
SELECT COALESCE(point,'\u672a\u53d7\u9a13') FROM test;<\/code><\/pre>\n\n\n
\u25c6Oracle<\/strong><\/p>\n\n\n
SELECT NVL(point,'\u672a\u53d7\u9a13') FROM test;<\/code><\/pre>\n\n\n\n
\u300cINSERT\u300d\u6587\u3067NULL\u5024\u3092\u767b\u9332\u3059\u308b<\/h2>\n\n\n
\u30c6\u30fc\u30d6\u30eb\u306b\u30c7\u30fc\u30bf\u3092\u8ffd\u52a0\u3059\u308b\u300cINSERT\u300d\u6587\u3067\u3001\u7279\u5b9a\u306e\u30ab\u30e9\u30e0\u306bNULL\u3092\u767b\u9332\u3057\u3066\u307f\u307e\u3057\u3087\u3046\u3002<\/p>\n
\u300c\u4e2d\u6751\u300d\u3068\u3044\u3046\u751f\u5f92\u3092\u8ffd\u52a0\u3057\u307e\u3059\u3002<\/p>\n
\u3010SQL\u5b9f\u884c\u30b3\u30fc\u30c9\u3011<\/strong><\/p>\n\n\n
INSERT INTO ITEM\n (id,name,point)\nVALUES\n ('8','\u4e2d\u6751',NULL);<\/code><\/pre>\n\n\n
\u300cSELECT\u300d\u6587\u3067\u30c7\u30fc\u30bf\u3092\u53c2\u7167\u3057\u307e\u3059\u3002<\/p>\n
\u3010\u5b9f\u884c\u7d50\u679c\u3011<\/strong><\/p>\n\n\n
id<\/strong><\/td>name<\/strong><\/td>point<\/strong><\/td><\/tr>
1<\/td>\u79cb\u5c71<\/td>80<\/td><\/tr>
2<\/td>\u4e45\u4fdd\u7530<\/td>100<\/td><\/tr>
3<\/td>\u4f50\u3005\u6728<\/td>NULL<\/td><\/tr>
4<\/td>\u4f50\u85e4<\/td>70<\/td><\/tr>
5<\/td>\u9234\u6728<\/td>NULL<\/td><\/tr>
6<\/td>\u7530\u4e2d<\/td>90<\/td><\/tr>
7<\/td>\u571f\u5c4b<\/td>60<\/td><\/tr>
8<\/td>\u4e2d\u6751<\/td>NULL<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
\u300cUPDATE\u300d\u6587\u3067NULL\u5024\u306b\u66f4\u65b0\u3059\u308b<\/h2>\n\n\n
\u30c6\u30fc\u30d6\u30eb\u306e\u30c7\u30fc\u30bf\u3092\u5909\u66f4\u3059\u308b\u300cUPDATE\u300d\u6587\u3067\u3001NULL\u5024\u306b\u5909\u66f4\u3057\u3066\u307f\u307e\u3057\u3087\u3046\u3002<\/p>\n
\u300c\u79cb\u5c71\u300d\u3055\u3093\u306e\u30c7\u30fc\u30bf\u3092\u66f4\u65b0\u3057\u307e\u3059\u3002<\/p>\n
\u3010SQL\u5b9f\u884c\u30b3\u30fc\u30c9\u3011<\/strong><\/p>\n\n\n
UPDATE\n ITEM\n SET\n CATEGORY = NULL\n WHERE id =1;<\/code><\/pre>\n\n\n
\u300cSELECT\u300d\u6587\u3067\u30c7\u30fc\u30bf\u3092\u53c2\u7167\u3057\u307e\u3059\u3002<\/p>\n
\u3010\u5b9f\u884c\u7d50\u679c\u3011<\/strong><\/p>\n\n\n
id<\/strong><\/td>name<\/strong><\/td>point<\/strong><\/td><\/tr>
1<\/td>\u79cb\u5c71<\/td>NULL<\/td><\/tr>
2<\/td>\u4e45\u4fdd\u7530<\/td>100<\/td><\/tr>
3<\/td>\u4f50\u3005\u6728<\/td>NULL<\/td><\/tr>
4<\/td>\u4f50\u85e4<\/td>70<\/td><\/tr>
5<\/td>\u9234\u6728<\/td>NULL<\/td><\/tr>
6<\/td>\u7530\u4e2d<\/td>90<\/td><\/tr>
7<\/td>\u571f\u5c4b<\/td>60<\/td><\/tr>
8<\/td>\u4e2d\u6751<\/td>NULL<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
\u300cNOT NULL\u300d\u3067\u5236\u7d04\u3059\u308b<\/h2>\n\n\n
\u300cNOT NULL\u300d\u3092\u7528\u3044\u308b\u3053\u3068\u3067\u4e2d\u8eab\u306bNULL\u5024\u3092\u6307\u5b9a\u3067\u304d\u306a\u3044\u3088\u3046\u306b\u3067\u304d\u307e\u3059\u3002<\/p>\n
\u3010SQL\u5b9f\u884c\u30b3\u30fc\u30c9\u3011<\/strong><\/p>\n\n\n
CREATE TABLE \u30c6\u30fc\u30d6\u30eb\u540d(\u30ab\u30e9\u30e0\u540d NOT NULL, ...);<\/code><\/pre>\n\n\n
\u3053\u306e\u5236\u7d04\u306e\u3042\u308b\u30ab\u30e9\u30e0\u306bNULL\u5024\u3092\u542b\u3080\u30ec\u30b3\u30fc\u30c9\u3084\u4e2d\u8eab\u3092\u672a\u6307\u5b9a\u306e\u30ab\u30e9\u30e0\u3092\u8ffd\u52a0\u3057\u3088\u3046\u3068\u3059\u308b\u3068\u3001\u300cError: NOT NULL constraint failed: user.name\u300d\u3068\u3044\u3046\u30a8\u30e9\u30fc\u8868\u793a\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n
SQL\u95a2\u9023\u8a18\u4e8b<\/h2>\n\n\n
\n