About phoenix to read and write less and less to write secondary index reading problems and spark an accumulator write-only, read-only variables to distinguish between broadcast

phoenix secondary index in two ways:

1, the global index: global index to know all the positions, fast search index, but not all of the data and write it in a so require network transmission. It is suitable to read write less.

2, local index: the data in the same region, since no fast write transmission local network. But knowing less so for less reading and writing.