Comparison
ORCvsParquet
ORC
the tables are in the other columnar format, the one that came out of the Hive world, with stripes instead of row groups.
A columnar file format contemporary with Parquet, with comparable capabilities and different vocabulary — stripes rather than row groups, and built-in lightweight indexes. Which one a platform uses is nearly always a historical accident of its Hadoop lineage rather than a live technical decision. Knowing the word matters mostly so that a stripe-related error message is legible.
Full entry →Parquet
the files are columnar with statistics in the footer, so the engine can skip whole chunks without reading them.
The de facto columnar file format for analytics: typed columns, per-chunk statistics, dictionary and run-length encoding, and a footer describing the layout. Its statistics are what make predicate pushdown work, which is why the same query can be fast or slow on identical data depending on how the files were written and sorted. It is a vendor-neutral name people say as a noun, which is why it is here and a console feature is not.
Full entry →