So I’m playing around with Google AppEngine (still!) trying to put together some kind of sensible use for it. AppEngine is neat-O, but it is also quite limited in what it can and can’t do. One of the most glaring problems (for my toy app) is the datastore query API, which has various restrictions, including:
Inequality Filters Are Allowed On One Property Only
Now this is pretty obviously an efficiency measure: retrieving on inequalities involves iterating along one index, and the datastore isn’t in the business of picking which one to iterate along. But its also really annoying if you actually want to do something which needs multiple inequalities.
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Posted by nickzoic 