This sample demonstrates use of queries in a distributed partitioned map, utilizing Constrained Tree Schemas (CTS) and applications (CTA) for extreme OLTP (XTP) concepts . eXtreme Scale is a highly scalable and partitionable grid . Generally, a key in an Object is mapped to a specific partition. This mapping can become complicated if the Objects have a relationship because they may not map to the same partition. Consider an example of two Objects, Customer and Order, with keys 1 and 2 respectively and a one-to-many relationship. It is possible that Customer is persisted in partition X and Order in partition Y. To ensure that both entities are co-located in the same partition, the Customer entity is identified as the root of the relationship (or schema). All entities related to the Customer entity are collocated in the same partition. Since all interactions with the Customer entity and its related entities are bound within a single partition (process), operations such as adding new orders and querying orders for the customer are very fast and scalable.
This sample demonstrates the EntityManager Query API .
- WebSphere eXtreme Scale version 126.96.36.199 or later
- The sample will only run in the standalone WebSphere eXtreme Scale installation, the trial version .
- Java Software Development Kit (JDK) version 1.5 or later
To install the sample follow these steps:
- Download the PartitionedEntities.zip file from the downloads section below.
- Extract the PartitionedEntities.zip file to the <ObjectGrid>/samples directory.
The <ObjectGrid> directory is the directory where the eXtreme Scale trial was extracted, or the ObjectGrid directory within a WebSphere eXtreme Scale product install.
Running the sample
The PartitionedEntities.zip contains the binary class files and the source files for running the queries. For details on running the sample, see the README.txt file located in the extracted directory. For details on running the sample in Eclipse, see the ECLIPSE_README.txt file also located in the extracted directory.
Please post any feedback on this sample as a comment on this page.
|PartitionedEntities.zip||55 kb||Mar 01, 2010|