Compression Setting

[benjaminwinger]

From #2004 (review).

For #2004 it would be helpful to have a runtime database option (e.g. ENABLE_COMPRESSION) for enabling/disabling compression.

I'm not entirely sure how we would want to implement such a thing, as it presumably should be a persistent setting, not just a setting for accessing the database like bufferPoolsize and maxNumThreads in the SystemConfig struct. That being said, since #2004 stores compression information per-chunk, it certainly would be possible to change the setting after the database has been created, it would just mean that the new setting would only affect new ColumnChunks (unless there is some re-processing done to update the existing data to match the new value of the setting).

[benjaminwinger]

Fixed by #2102