Hello , 

I have a problem with API. 
I want to get the diff between one revision and its previous revision. I use api like this:

"https://en.wikipedia.org/w/api.php?action=query&format=json&prop=revisions&titles=J.+Robert+Oppenheimer&rvprop=ids%7Ctimestamp%7Cflags%7Ccomment%7Cuser&rvlimit=10&rvdiffto=prev"

But the results only return the "diff" of the first two revisions, the others are “notcatched":
             {
                        "revid": 715123287,
                        "parentid": 714799929,
                        "user": "SnoozeKing",
                        "timestamp": "2016-04-13T21:07:34Z",
                        "comment": "",
                        "diff": {
                            "notcached": ""
                        }
                    },
                    {
                        "revid": 714799929,
                        "parentid": 712263801,
                        "minor": "",
                        "user": "Smithderek2000",
                        "timestamp": "2016-04-11T22:43:14Z",
                        "comment": "Removed unclear pronoun",
                        "diff": {
                            "notcached": ""
                        }
                    },

Why? If someone know, please reply me, I really need your help!!!
Thanks a lot!!!


--

Zhang Shiyue

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E-mail: byryuer@gmail.com, yuer3677@163.com

State Key Laboratory of Networking and Switching Technology

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Beijing University of Posts and Telecommunications

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