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I'm very new to grid computing, and would appreciate help on the following:
Say I have 2 subsidiary companies, belonging to the same corporation, and I want to manage their personnel database. Now, most of the time, this can be 2 separate instances of the application, unrelated and un-clustered: each company will manage its own people, on its own application server and its own database, with no interest in the other company. I don't want to put them on a cluster and replicate data, because it's slower, harder to manage, and with little benefit (I don't need backup nor fail-over).
However, once a week I want to issue a "shared" report on the 2 databases, as if they were one (running statistics on salaries, sick days, etc - for the 2 companies together). I can make sure the databases are logically easy to merge (e.g. each company has its own range of IDs, to avoid conflicts).
Are there any tools to issue such 'merged' reports with Java? Either in JDBC level (JDBC driver that connects to 2 databases simultaneously), or some higher level grid-computing tools? Thanks.
I don't see this as necessisarily a Grid problem - assuming you can write one program that can access both databases.
If security or other considerations require that a separate process on each servers be used to access the data then you do have a distributed computing problem.
I would be thinking in terms of defining an output format from each database that lends itself to merging, with the merge occuring in a separate step rather than trying to simultaneously run queries in both.