Platonides schreef:
Why is it so? Normal diffs don't have such problem: http://en.wikipedia.org/w/index.php?diff=prev&oldid=13135969
With normal UI diffs, you can only get one diff at a time. Through the API, you can get hundreds of revisions in one request. Looking up the previous revision for each of them means hundreds of database queries, which will kill the database.
Note: getting diffs through the API is now possible (see the "Getting differences between revisions" thread in this list).
Roan Kattouw (Catrope)