diff --git a/src/flow/src/compute/render/reduce.rs b/src/flow/src/compute/render/reduce.rs index 72f3eac5e6..fe8f64560b 100644 --- a/src/flow/src/compute/render/reduce.rs +++ b/src/flow/src/compute/render/reduce.rs @@ -344,8 +344,13 @@ fn reduce_distinct_subgraph( /// /// the data being send is just new rows that represent the new output after given input is processed /// -/// i.e: for example before new updates comes in, the output of query `SELECT sum(number) FROM table` -/// is 10, and after new updates comes in, the output is 15, then the new row being send is (15, now, 1) +/// i.e: for example before new updates comes in, the output of query `SELECT sum(number), count(number) FROM table` +/// is (10,2(), and after new updates comes in, the output is (15,3), then the new row being send is ((15, 3), now, 1) +/// +/// while it will also update key -> accums's value, for example if it is empty before, it will become something like +/// |offset| accum for sum | accum for count | +/// where offset is a single value holding the end offset of each accumulator +/// and the rest is the actual accumulator values which could be multiple values fn reduce_accum_subgraph( arrange: &ArrangeHandler, distinct_input: &Option>,