Miles Cole lays out a recommendation:
Liquid Clustering was already a better abstraction than static partitioning due to its flexible nature. Fabric Spark Runtime 2.0 fixes the part that had me actively cautioning customers to reconsider blindly adopting it: the cost of maintaining the layout.
In Runtime 1.3 (Delta 3.2) a small append followed by
OPTIMIZEwould rewrite every file in a partial Z-Cube. In Runtime 2.0, the incremental strategy only touches files that are unclustered, small, or carrying a high density of deletion vectors. That changes Liquid Clustering from an occasional, potentially expensive maintenance operation into something that works beautifully with workloads of any shape and with adjacent layout optimizations. Batch or streaming writes. Auto Compaction and/or Fast Optimize. With the new incremental strategy, Liquid Clustering is highly compatible and highly efficient, and should now take its rightful place as the de facto new data layout strategy.
Read on to learn more about what Liquid Clustering is, how it works, and why you should think about it if you’re using Fabric Spark Runtime 2.0.
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