The most common complaints [about batch processing]: No partial answers – you have to wait for the entire batch to finish. For big batches this can take a lot of time. Hardware requirements – because they process everything at once, batch systems typically require more hardware (such as memory, disk and CPU) than streaming systems which can process a transaction and then throw it away. Limited ad-hoc capabilities (more on this later). All or nothing – Any change in the data usually requires the entire batch to be recalculated.
via NoSQL databases