Thanks Wolfram for sharing your thoughts and i very much appreciate it. I was also thinking of storing business data as a blob and using indexes only to select that data. Thanks for confirming that this approach is working very well.
I have one more question regarding namespaces and entity groupings. Lets assume 1. *entity1, entity2* are in *namespace ns1 * 2. *entity3, entity4* are in *namespace ns2* 3. *entity1, entity3* has *parent p1 * 4. *entity2, entity4 *has *parent p2* are entities 1 and 3 in different groups from a transaction perspective because they belong to different namespaces? thanks, dhanunjay On Thu, Feb 4, 2016 at 11:58 AM, Wolfram Gürlich <[email protected]> wrote: > One thing that makes the datastore stand out is that it doesn't store > meta data about your kinds. Thats's why there isn't a limit to the number > of entity kinds or namespaces you can have. > 200 kinds is no problem from that perspective. > > Namespaces make your life much easier. Your 2nd approach is pretty much > what appengine does on the inside when you use namespaces. > > The limit on custom indexes is a serious problem however. Our solution was > to not use them at all. We use single indexed properties instead and manage > our composite indexes on top of that. That's much less pain than it may > sound at first. > > To become a happy datastore user you must overcome relational thinking. > There's more to it than to just stop thinking in terms of "tables". You > should design for a more coarse-grained data scheme. In general that means > identifying the entities that will almost always be used together - like an > order and its order items. Store them as closely together as you can. > Entity groups are a good start but also take a look at embedded entities. > > What we did is to store all business data as JSON Blobs inside entities > and use regular properties for the *sole* purpose of indexing. That has > been working out *very* well for us. > > Regards, > Wolfram > > > -- > You received this message because you are subscribed to a topic in the > Google Groups "Google App Engine" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/google-appengine/H03vcmqrkZw/unsubscribe > . > To unsubscribe from this group and all its topics, send an email to > [email protected]. > To post to this group, send email to [email protected]. > Visit this group at https://groups.google.com/group/google-appengine. > To view this discussion on the web visit > https://groups.google.com/d/msgid/google-appengine/de93c24c-f2eb-4300-9104-8c17f6b10459%40googlegroups.com > <https://groups.google.com/d/msgid/google-appengine/de93c24c-f2eb-4300-9104-8c17f6b10459%40googlegroups.com?utm_medium=email&utm_source=footer> > . > > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/google-appengine. To view this discussion on the web visit https://groups.google.com/d/msgid/google-appengine/CAHwUyAr7nNdOfroZcV_UEEptUTRNQ5aYCMQEApoEiwThJh%3D2uQ%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
