{"provider_name":"Hatena Blog","html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Fkwatch.hatenadiary.org%2Fentry%2F20081214%2F1229260071\" title=\" DataMapper \u3067\u306e 1+N \u554f\u984c - k\u306a\u3093\u3068\u304b\u306e\u65e5\u8a18\" class=\"embed-card embed-blogcard\" scrolling=\"no\" frameborder=\"0\" style=\"display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;\"></iframe>","blog_title":"k\u306a\u3093\u3068\u304b\u306e\u65e5\u8a18","description":"DataMapper \u3067\u306f\u3001\u3044\u308f\u3086\u308b 1+N \u554f\u984c\u306f\u8d77\u3053\u3089\u306a\u3044\u3068\u8a00\u308f\u308c\u3066\u3044\u308b\u3002\u305f\u3068\u3048\u3070\u6b21\u306e\u3088\u3046\u306a\u4f8b\u3002ActiveRecord \u306a\u3089 1+N \u30b3\u306e SELECT \u6587\u304c\u767a\u884c\u3055\u308c\u308b\u3051\u3069\u3001DataMapper \u3067\u306f 1+1 \u30b3\u306e SELECT \u6587\u3060\u3051\u3092\u767a\u884c\u3059\u308b\u3002 $ merb -i irb> IRB.conf[:MAIN_CONTEXT].echo = false # \u30a8\u30b3\u30fc\u30d0\u30c3\u30af\u3092\u5207\u308b irb> employees = Employee.all irb> employees.each {|emp| p emp.department } # 1+1 \u30b3\u306e SQL \u6587 ~ SELECT `id`, `n\u2026","width":"100%","published":"2008-12-14 22:07:51","blog_url":"https://kwatch.hatenadiary.org/","provider_url":"https://hatena.blog","height":"190","author_name":"kwatch","version":"1.0","categories":["merb"],"title":" DataMapper \u3067\u306e 1+N \u554f\u984c","url":"https://kwatch.hatenadiary.org/entry/20081214/1229260071","author_url":"https://blog.hatena.ne.jp/kwatch/","type":"rich","image_url":null}