I'm python but i think it is in java possible too, for exampl. based on a part of the url load the right database layer module. To change the google datastore entities you go over all and add or empty a property (delete), in admin there is an remove all function. Keep in mind that datastore writes are restricted for master/slave 5 writes, high replication 1 write p/s. Use memcache or taskqueue's to manage the load. gr wim
2011/1/17 Steel City Phantom <[email protected]>: > im writing a new app. currently its a LAMP app, heavy on AJAX, but once > this prototype is done and running i want to rewrite it as an enterprise > level application. im looking at GAE as a back end (more because ive never > done it before and it looks cool than anything else, free hosting doesn't > hurt either) but im struggling with the data store stuff. the biggest > problem i have so far is changing the data store once its deployed. here is > what i understand so far, tell me where im wrong cuz im sure i am > 1 - create your entity objects (this is java) > 2 - when deployed, GAE will create the data store based on the entity > objects in your WAR file. > 3 - use them with googles app engine sql language. > now, if i want to change the model > update your entity objects with your new fields or whatever and deploy. now > GAE should maintain the existing data and update the objects. > or am i completely off base in thinking like a relational database system. > is it more as a base relational system that stores blobs and i can store > whatever i want in them? > second, > what if i have a drastic change to the data model that requires some > translation sql to implement? is there some kind of screen where i can > query and update the existing data model manually and translate the data > into the new model or do i have to do it in the application code. > > -- > You want it fast, cheap, or right. Pick two!! > > -- > You received this message because you are subscribed to the Google Groups > "Google App Engine" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/google-appengine?hl=en. > -- gr Wim den Ouden Custom applications, https://e-comm.appspot.com/ Free open source E-commerce framework (web) apps, http://code.google.com/p/relat/ Gae developer tips, http://code.google.com/p/relat/wiki/gaetips -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
