Reporting solutions on AppEngine

Actually, reporting has two separated tasks:

1. Query data from one or more Kind(s)
2. Rendering data into PDF, Excel, HTML format

For question #1:

App开发者_StackOverflowEngine does not support JOIN. Thus what is best solution for this purpose?

For question #2:

Is there any solution which are able to run on AppEngine?

Thanks

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1. If you have, for example, a customer and their orders, include the orders data in the same record as the customer instead of using a relational join to grab it. BigTable allows you to store arbitrary muti-value attributes in any column.
2. A simple solution (assuming you want to use JSP) is DisplayTag.