系统与数据库2019hal.inria.fr
语义网与关联数据研究二十年综述
A Survey of the First 20 Years of Research on Semantic Web and Linked Data
进阶 · 约 90 分钟读完前置知识：RDF 与 OWL 基础、SPARQL、Web 技术发展史
导读
这篇论文是对语义网与关联数据领域 20 年研究的综述，回顾了 RDF、OWL、SPARQL 等技术体系的发展脉络与研究成果。评论区的讨论焦点则是语义网在现实中的实际落地情况——多数人认为其理念虽好，但从未真正被主流 Web 采用。
HN 关注点：HN 读者长期关注语义网“雷声大雨点小”的历史：理念宏大但工业落地失败，这篇综述引发了对其成败原因的回顾与争论。
后来怎么样
作为领域二十年研究的系统综述，成为语义网与关联数据方向常被引用的参考文献，但语义网本身未能被主流 Web 采用，其愿景在实践中基本落空。
HN 评论精选
这几条评论里：质疑 2 补充 1 亲历 1
质疑现实 Web 正在变得愈发不语义化，语义网败于过度复杂的委员会设计
RSS/Atom 正在慢慢被杀死；XHTML 被一堆只能靠单一解析器处理的垃圾取代；HTML 整体上变成了可执行 JavaScript 的渲染层。做了多年系统集成，我只见过一个 HATEOAS Web 服务，而且它现在正被 GraphQL 替换。我喜欢语义化内容的理念，但它正被那些委员会设计的过度复杂的抽象和格式压得喘不过气。事实上，我们实际使用的 Web 正在一年比一年更不语义化。我希望有人能重新标准化 XML，去掉那些复杂的边界情况垃圾、改进命名空间处理，让它重新被用于文档——JSON 不是好的文档格式，而现在大家都在用 JSON 重新发明 XML。比如说我想自定义一个概念放到网页上，在 HTML5 里没有命名空间的情况下，现在甚至有“官方”的正确做法吗？
gambler查看英文原文
RSS/Atom is being slowly killed. XHTML was replaced by a pile or junk that can only be parsed by a single parser. HTML in general became a rendering layer for executable JavaScript. After years of doing integrations, I've seen one(!) HATEAOS web service and it's being replaced by GraphQL right now. I like the idea of having semantic content, but it is suffocating under the weight of all the overcomplicated designed-by-committee abstractions and formats. In fact, the real web that we're using is becoming less and less semantic every year. I wish someone re-standardized XML without all the complicated edge case garbage and with better handling of namespaces. So it would actually get used for documents again. JSON is not a good document format, and it seems everyone is busy re-inventing XML in JSON right now. Let's say I want to define my own concept and put it on a web page. Is there even an "official" way to do it right now, without namespaces in HTML5? Theoretical example: <html> <head> <concept tag="computer-game" guid="c1a3e0cb-5872-4e5a-8dce-b8afc00772db" /> <concept attribute="year-published" guid="ba073188-8bd6-47a7-9065-eb55c4a8b908" /> </head> <body> <computer-game year-published="1993">Doom</computer-game> </body> </html> Simple, isn't it? I'm not aware of anything of this sort.
补充综述视野太窄，相关技术生态的进展其实比人们认为的更多
从应用开发者的角度看，这篇综述遗漏的是 OMG 等组织也在追求非常类似的目标。同样，RDF 数据可以配合 F-Logic、XSB Prolog 以及大量非 SPARQL 工具使用；文档数据库和图数据库也在与 SPARQL 数据库竞争（很多语义网难民转用了 Couchbase 或 ArangoDB）。我希望看到这些与 RDF 并排比较，那样就会发现我们取得的进展比大多数人以为的要多。
PaulHoule查看英文原文
From the viewpoint of an application creator what I find missing from here is that very similar goals have been pursued by the OMG and other organizations. Similarly RDF data works with F-Logic, XSB Prolog and a wide range of non-SPARQL tools. There has also been a proliferation of document and graph databases that compete w/ SPARQL databases. (Many sebweb refugees use Couchbase or ArangoDB) I'd like to see that side-by-side with RDF because then you'd see we've made more progress than most people think.
亲历亲历：语义网对用例匹配要求极高，多数组织根本执行不动
我曾就职于一家被语义网理念打动、在工具和培训上做了初期投入的公司。我觉得这些概念很有意思，但负责落地的团队在尝试了大约六个月后，就放弃了让它们适配自己用例的努力。我理解它对某些用例可能很强大，但要让它跑起来所需的投入和细致程度，恐怕超出了很多组织的执行能力。我的印象是，这就像决定每天早上用功率天平称自己的体重——工具和用例必须匹配，而对很多组织来说这根本不是合适的工具。
chasingthewind查看英文原文
I worked at a company that got sold on Semantic Web and made an initial investment in tools and training. While I found the concepts intriguing, the teams tasked with making it work gave up after about six months of trying to make it work with the use case they had. I understand that it can be a powerful set of concepts for certain kinds of use cases but it feels like the level of dedication and care needed to make it work is probably beyond many organizations' ability to execute. The impression I got was that it was like deciding to use a Kibble Balance [0] to weigh yourself in the morning. You have to match the use case to the tool and for many organizations this simply will not be the right tool. [0] https://en.wikipedia.org/wiki/Kibble_balance
质疑语义网已死，去中心化 Web 本身也被巨头围墙花园取代
语义网已经死了，它从来就没真正成过气候。就连普通的去中心化 Web 也基本消亡了，被巨头们的围墙花园取代：95% 的内容都在 Facebook、Google、Twitter、Instagram、YouTube、Netflix、Reddit、Twitch、Medium 等少数平台里，剩下的只是个几乎无人问津的骨架。语义网即使技术再好，也已经不再必要或有用。
planck01查看英文原文
The Semantic Web is dead. It was never really something. Even the regular decentralized Web has mostly died. It was replaced by mega corporations' walled gardens. 95% of content is in there; in Facebook, Google, Twitter, Instagram, Youtube, Netflix, Reddit, Twitch, Medium and a few small others. The rest is a skeleton barely being touched. The Semantic Web isn't even necessary or useful anymore, even if its technology were good.
历次讨论
- 2019Hacker News 讨论帖149 分 · 48 评
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