2 Commits

Author	SHA1	Message	Date
Matvey Arye	300db8594a	Fix detoasting bug and add tests ... Previously, the detoasting in Array was incorrect and so the compressed table stored pointers into the toast table of the uncomoressed table. This commit fixes the bug and also add logic to the test to remove the uncompressed table so such a bug would cause test failures in the future.	2019-10-29 19:02:58 -04:00
Joshua Lockerman	584f5d1061	Implement time-series compression algorithms ... This commit introduces 4 compression algorithms as well as 3 ADTs to support them. The compression algorithms are time-series optimized. The following algorithms are implemented: - DeltaDelta compresses integer and timestamp values - Gorilla compresses floats - Dictionary compression handles any data type and is optimized for low-cardinality datasets. - Array stores any data type in an array-like structure and does not actually compress it (though TOAST-based compression can be applied on top). These compression algorithms are are fully described in tsl/src/compression/README.md. The Abstract Data Types that are implemented are - Vector - A dynamic vector that can store any type. - BitArray - A dynamic vector to store bits. - SimpleHash - A hash table implementation from PG12. More information can be found in src/adts/README.md	2019-10-29 19:02:58 -04:00