Definition
Type that determines how data will be laid out as file and stored, inside a def~table.
#todo verify
Following table summarizes the trade-offs between these two dataset table types
Trade-off | def~copy-on-write (COW) | def~merge-on-read (MOR) |
---|---|---|
Data Latency | Higher | Lower |
Update cost (I/O) | Higher (rewrite entire def~table parquet) | Lower (append to `delta log`) |
Write Amplification | Higher | Lower (depending on compaction strategy to the def~table parquet) |
Query/Read Amplification | Lower/Zero | Higher (merging base and deltas on the fly) |