At this point of writing, I am reading the Hadoop the definitive Guide, 3rd Edition from Oreilly. I thought I capture some information down from what I learn.
Here is a summary of the difference between Traditional RDMS and MapReduce
| Traditional RDBMS | MapReduce | |
|---|---|---|
| Data size | Gigabytes | Petabytes |
| Access | Interactive and batch | Batch |
| Updates | Read and write many times | Write once, read many times |
| Structure | Static schema | Dynamic schema |
| Integrity | High | Low |
| Scaling | Nonlinear | Linear |