Summary:
Replacement of #2147
The change was squashed due to a lot of conflicts.
Closes https://github.com/facebook/rocksdb/pull/2194
Differential Revision: D4929799
Pulled By: siying
fbshipit-source-id: 5cd49c254737a1d5ac13f3c035f128e86524c581
Summary:
Experiments on column-aware encodings. Supported features: 1) extract data blocks from SST file and encode with specified encodings; 2) Decode encoded data back into row format; 3) Directly extract data blocks and write in row format (without prefix encoding); 4) Get column distribution statistics for column format; 5) Dump data blocks separated by columns in human-readable format.
There is still on-going work on this diff. More refactoring is necessary.
Test Plan: Wrote tests in `column_aware_encoding_test.cc`. More tests should be added.
Reviewers: sdong
Reviewed By: sdong
Subscribers: arahut, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D60027
