3 ms·
Database vendors add Google's MapReduce
- gaius 18y agoI'm unimpressed. Firstly,it isn't clear to me what you might do in Java instead of doing it in SQL. Java isn't a query language. Secondly, parallelization has been available in mainstream databases for a long time now. If you have partitioned your Oracle table n ways and have m query slave processes, Oracle will happily "map" your query onto many workers then "reduce" (merge) it and give it back to you as a single result set or even a single row if you are using aggregation functions. You don't need to do anything special, the query optimizer will take care of it. The only person who needs to know what's happening under the hood is the DBA whose job it is to understand all this stuff. And while I'm here, I'm pretty sure Google invented neither map nor reduce. They've been in functional languages like, forever.