Azure Synapse Analytics 监视器行组跳过

Question

For reference i'm using a CCI table (Hash) I'm looking for a solution to monitor if, for a query with a WHERE predicate on my Hash, Synapse is well skipping the invalid rowgroups.

Answer 1

For a Hash-distributed table Synapse will eliminate Distributions, not rowgroups. It's the partition scheme and CCI order that control row group skipping. And that should be evident in the execution plan .

For a CCI, each table has multiple (60) Distributions. Each Distribution has one or more Partitions. Each Partition has one or more Row Groups. Each Row Group has up to 1 million rows.

For Heaps and Clustered Index tables it's the same, except each Partition has one Heap or Clustered Index.