TLDR Tech / Data
MOR Isn't a Storage Optimization. It's an Architectural Shift
Instead of synchronously rewriting entire files on every mutation (Copy-On-Write), MOR (Merge-On-Read) appends changes to log files and defers the expensive merge/compaction work to a background process, effectively time-shifting optimization from write time to a separate, controllable schedule. This design better supports high-frequency streaming updates and CDC workloads, though it introduces tradeoffs in read amplification and compaction management.
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