Clarification Needed on .show queryplan Output Fields in ADX

Below is an explanation for each field as understood based on current internal references and community discussion:

• plansize
  This represents the overall size of the query plan that has been compiled. Think of it as the total “footprint” of the execution plan. It’s useful as a rough indicator of plan complexity or memory overhead during query processing.

• relopsize
  This field details the cumulative size (or memory footprint) taken up by the relational operators in the plan. In other words, it shows how much of the overall plan complexity is due to the individual relational operator nodes that make up the query’s logic.

• replotree
  This provides a hierarchical text representation of the relational operator tree—the detailed breakdown of how the relational operators are arranged. It’s essentially a structural view of the query’s execution plan that can help pinpoint which parts of the plan might be contributing most to the complexity or performance overhead.

Keep in mind that the public documentation for these fields might be limited. When debugging query performance with these values, you can compare them across queries or different versions of a query to see how modifications affect complexity and resource usage.