{"author_url":"https://blog.hatena.ne.jp/Naotsugu/","blog_url":"https://blog1.mammb.com/","blog_title":"A Memorandum","published":"2025-02-25 00:00:00","image_url":null,"description":"\u306f\u3058\u3081\u306b Oracle \u306b\u304a\u3051\u308b\u7a7a\u6587\u5b57\u306e\u6271\u3044 UNKNOWN \u306e\u6271\u3044 Oracle \u3068 PostgreSQL \u53cc\u65b9\u3067\u52d5\u304fSQL \u306f\u3058\u3081\u306b \u7a7a\u6587\u5b57\u3068 null \u3092\u533a\u5225\u3057\u306a\u3044 Oracle \u3068\u3001PostgreSQL \u306e\u3088\u3046\u306b''\u7a7a\u6587\u5b57\u3068 null \u3092\u533a\u5225\u3059\u308b\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306e\u53cc\u65b9\u306b\u5bfe\u5fdc\u3059\u308b\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u306b\u3057\u305f\u3044\u5834\u5408\u3092\u8003\u3048\u307e\u3059\u3002 val \u306b\u5024\u304c\u7121\u3044\u30ec\u30b3\u30fc\u30c9\u306f\u3001Oracle \u3067\u3082 PostgreSQL \u3067\u3082\u3001\u4ee5\u4e0b\u306eSQL\u3067\u53d6\u5f97\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002 select * from example where (val is null or val = ''); \u9006\u306b val \u306b\u5024\u304c\u6709\u308b\u30ec\u30b3\u30fc\u30c9\u3092\u53d6\u5f97\u3059\u308b\u5834\u5408\u3001\u2026","author_name":"Naotsugu","provider_name":"Hatena Blog","provider_url":"https://hatena.blog","height":"190","version":"1.0","width":"100%","type":"rich","categories":[],"url":"https://blog1.mammb.com/entry/2025/02/25/000000","title":"Oracle \u7a7a\u6587\u5b57\u6bd4\u8f03\u306e\u5384\u4ecb","html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Fblog1.mammb.com%2Fentry%2F2025%2F02%2F25%2F000000\" title=\"Oracle \u7a7a\u6587\u5b57\u6bd4\u8f03\u306e\u5384\u4ecb - A Memorandum\" class=\"embed-card embed-blogcard\" scrolling=\"no\" frameborder=\"0\" style=\"display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;\"></iframe>"}