Hi folks, I'm new to Drill and find "Drill also provides an execution layer that performs SQL processing directly on columnar data without row materialization" and "vectorization in Drill allows the CPU to operate on vectors" on https://drill.apache.org/architecture/ page.
I'm really curious about how these are implemented in Drill, after some search in the current code base, I could only find parquet files could be read in as vectors, how are these vectors handled then in `vectorized` manner? Could someone nicely point out where I can find more information/code on this? Thanks in advance. Yijie
