Right now we clone product values for incremental queries, even ones without any mutative operations like projections. This is because each execution plan owns its delta tables, and each delta table in turn owns its product values. However there's no need for an execution plan to own the delta values that it operates on, unless it must construct new values as is the case for projections.
In the profile above, these clones account for roughly 20-25% of the evaluation of incremental table selects.
joshua-spacetime
commented
5 months ago
Right now we clone product values for incremental queries, even ones without any mutative operations like projections. This is because each execution plan owns its delta tables, and each delta table in turn owns its product values. However there's no need for an execution plan to own the delta values that it operates on, unless it must construct new values as is the case for projections.
In the profile above, these clones account for roughly 20-25% of the evaluation of incremental table selects.