What jar are 开发者_开发问答files needed for Google App engine datastore via JPA and JDO?The Google App Engine platform provides Java persistence (JDO or JPA) to its BigTable datastore using the datan
My understanding of detach copy is that it makes a copy of your object so that you can make changes to it without the PersistenceManager noticing.
With JDO, when should I use detachCopy and when should I use makeTransient? Wha开发者_如何学Got exactly do each of them do?I\'m sure we wrote docs about those things ...
I am building a web app using GAE Java. I have a class that uses a Long ID (generated by appengine) as its primary key.
Most of the docs for Google App Engine are written for JDO. Only one pa开发者_如何学Goge of docs are devoted to using JPA. Is this because JDO is more suited to App Engine or was there some other reas
I am trying to develop a Java application which merges data from multiple data source basically RDBMS. The scenario is some thing like this.
I am building an app based on google app engine (Java) using JDO for persist开发者_StackOverflow中文版ence.
In the old days we used to access the database through stored procedures.They were seen as `the better\' way of managing the data.We keep the data in the database, and any language/platform can access
Using JDO on GAE, I\'m using a simple database transaction code block like below. What is a good way to retry/recover from a thrown java.sql.SQLException: Concurre开发者_StackOverflow中文版nt Modific
My understanding is that the original incarnation of JDO required the use of XML files to describe the metadata but I see that the most recent version allows annotations.
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