HBase has a powerful feature called coprocessors, which we will briefly explain to raise awareness with the reader, but a deeper coverage is outside the scope of this book.
One of the tenets of large-scale data processing is to ensure that the analytics are executed as close to the data layer as possible in order to avoid moving large amounts of data to where the processing is being done. HBase filters are an example of server-side processing that reduces the amount of data flowing back into the client.
HBase offers a set of constructs called coprocessors that allow for arbitrary server-side processing. Since this is arbitrary code running without any sandboxing within the RegionServers, they can also be a source of instability ...
