{"title":"LEFT JOIN","categories":["PostgreSQL"],"version":"1.0","blog_title":"\u8eca\u8f2a\u306ex\u767a\u660e ~B.G's Blog~","provider_url":"https://hatena.blog","blog_url":"https://bg1.hatenablog.com/","description":"LEFT JOIN\u306f\u3001\u7d50\u5408\u5143\u306e\u30c6\u30fc\u30d6\u30eb(\u5de6\u306e\u30c6\u30fc\u30d6\u30eb\u3068\u547c\u3076)\u306b\u3042\u308b\u884c\u306f\u3059\u3079\u3066\u6b8b\u3057\u3001\u7d50\u5408\u5148\u306e\u30c6\u30fc\u30d6\u30eb(\u53f3\u306e\u30c6\u30fc\u30d6\u30eb\u3068\u547c\u3076)\u306b\u4e00\u81f4\u3059\u308b\u30c7\u30fc\u30bf\u304c\u306a\u3044\u5834\u5408\u306f\u3001NULL\u3092\u88dc\u3063\u3066\u7d50\u5408\u7d50\u679c\u306b\u542b\u3081\u308b\u3002https://www.postgresql.jp/docs/9.4/queries-table-expressions.html postgresdb1=# SELECT * FROM users; id | name ----+------- 1 | Alice 2 | Bob 3 | Carol (3 \u884c) postgresdb1=# SELECT * FROM test_results; id | use\u2026","author_name":"BG1","url":"https://bg1.hatenablog.com/entry/2025/07/26/210000","height":"190","published":"2025-07-26 21:00:00","image_url":null,"type":"rich","author_url":"https://blog.hatena.ne.jp/BG1/","provider_name":"Hatena Blog","html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Fbg1.hatenablog.com%2Fentry%2F2025%2F07%2F26%2F210000\" title=\"LEFT JOIN - \u8eca\u8f2a\u306ex\u767a\u660e ~B.G&#39;s Blog~\" class=\"embed-card embed-blogcard\" scrolling=\"no\" frameborder=\"0\" style=\"display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;\"></iframe>","width":"100%"}