fix(tesseract): multi_stage reduce_by no-ops on type:time dimensions

rust/cube/cubesqlplanner/cubesqlplanner/src/planner/planners/multi_stage/member_query_planner.rs

@@ -470,19 +470,55 @@ impl MultiStageMemberQueryPlanner {
         reduce_by: &Vec<Rc<MemberSymbol>>,
         group_by: &Option<Vec<Rc<MemberSymbol>>>,
     ) -> Vec<Rc<MemberSymbol>> {
+        // Match a projected query dimension `d` against a measure-level
+        // `reduce_by` / `group_by` entry `m`, honouring the user's
+        // granularity intent on `m`:
+        //
+        // - If `m` carries an explicit granularity (e.g.
+        //   `<time_dim>.quarter` resolves to a `TimeDimensionSymbol` with
+        //   `has_granularity() == true`), match strictly on `full_name`. A
+        //   `group_by: [<time_dim>.quarter]` should keep only the
+        //   `_quarter` projection in PARTITION BY, not sibling granularities
+        //   of the same base time dim.
+        //
+        // - Otherwise (bare reference: plain `DimensionSymbol`, or
+        //   `TimeDimensionSymbol` with no granularity), match across
+        //   granularities by unwrapping both sides to their base symbol. A
+        //   `reduce_by: [<time_dim>]` should exclude the time dim from
+        //   PARTITION BY regardless of the projection's granularity suffix
+        //   — see cube-js/cube#10854: without unwrap, the `_day` /
+        //   `_month` / etc. suffix on `TimeDimensionSymbol::full_name`
+        //   caused string-equality mismatch and the time dim silently stayed
+        //   in PARTITION BY, collapsing the window to one-row partitions.
+        fn matches_partition_member(d: &Rc<MemberSymbol>, m: &Rc<MemberSymbol>) -> bool {
+            let m_has_explicit_granularity = matches!(
+                m.as_ref(),
+                MemberSymbol::TimeDimension(td) if td.has_granularity()
+            );
+            if m_has_explicit_granularity {
+                d.has_member_in_reference_chain(m)
+            } else {
+                let base = |x: &Rc<MemberSymbol>| match x.as_ref() {
+                    MemberSymbol::TimeDimension(td) => td.base_symbol().clone(),
+                    _ => x.clone(),
+                };
+                base(d).has_member_in_reference_chain(&base(m))
+            }
+        }
+
         let dimensions = self.all_dimensions();
         let dimensions = if !reduce_by.is_empty() {
             dimensions
                 .into_iter()
-                .filter(|d| !reduce_by.iter().any(|m| d.has_member_in_reference_chain(m)))
+                .filter(|d| !reduce_by.iter().any(|m| matches_partition_member(d, m)))
                 .collect_vec()
         } else {
             dimensions
         };
         let dimensions = if let Some(group_by) = group_by {
             dimensions
                 .into_iter()
-                .filter(|d| group_by.iter().any(|m| d.has_member_in_reference_chain(m)))
+                .filter(|d| group_by.iter().any(|m| matches_partition_member(d, m)))
                 .collect_vec()
         } else {
             dimensions

rust/cube/cubesqlplanner/cubesqlplanner/src/test_fixtures/schemas/yaml_files/common/integration_multi_stage.yaml

@@ -134,6 +134,13 @@ cubes:
                 - orders.status
                 - orders.category
 
+          - name: amount_reduce_created_at
+            type: sum
+            sql: "{CUBE.total_amount}"
+            multi_stage: true
+            reduce_by:
+                - orders.created_at
+
           - name: amount_group_by_status
             type: sum
             sql: "{CUBE.total_amount}"

rust/cube/cubesqlplanner/cubesqlplanner/src/tests/integration/multi_stage/group_by.rs

@@ -98,3 +98,41 @@ async fn test_group_by_equals_query_dims() {
         insta::assert_snapshot!(result);
     }
 }
+
+#[tokio::test(flavor = "multi_thread")]
+async fn test_group_by_time_dim_multiple_granularities() {
+    let ctx = create_context();
+
+    // Regression test mirroring the BigECommerce postgres-driver case (see
+    // packages/cubejs-testing-drivers/src/tests/testQueries.ts
+    // "multi-stage group by time dimension"). The query projects two
+    // granularities of the same time dim (month + week), while the measure
+    // `amount_group_by_status_time` has `group_by: [status, created_at.month]`
+    // — only the month granularity should stay in PARTITION BY.
+    //
+    // Expected: every (month, week) row reports the per-month grand total
+    // (Jan=500, Feb=750, Mar=1000), NOT the per-week sum. If `group_by`
+    // matched via TimeDimensionSymbol → base unwrapping, the week granularity
+    // would also stay in PARTITION BY and the result would collapse to
+    // per-(month, week) sums.
+    let query = indoc! {r#"
+        measures:
+          - orders.amount_group_by_status_time
+        time_dimensions:
+          - dimension: orders.created_at
+            granularity: month
+            dateRange:
+              - "2024-01-01"
+              - "2024-03-31"
+          - dimension: orders.created_at
+            granularity: week
+        order:
+          - id: orders.created_at
+    "#};
+
+    ctx.build_sql(query).unwrap();
+
+    if let Some(result) = ctx.try_execute_pg(query, SEED).await {
+        insta::assert_snapshot!(result);
+    }
+}

rust/cube/cubesqlplanner/cubesqlplanner/src/tests/integration/multi_stage/reduce_by.rs

@@ -120,3 +120,43 @@ async fn test_reduce_by_with_time() {
         insta::assert_snapshot!(result);
     }
 }
+
+#[tokio::test(flavor = "multi_thread")]
+async fn test_reduce_by_time_dim() {
+    let ctx = create_context();
+
+    // Regression test for cube-js/cube#10854: `reduce_by: [<time_dim>]` was
+    // silently ignored because `TimeDimensionSymbol::full_name` carries a
+    // granularity suffix (defaulting to "_day" even with no granularity)
+    // while the reduce_by entry resolves to a base DimensionSymbol without
+    // the suffix — string equality at the comparison site failed and the
+    // time dim stayed in PARTITION BY, collapsing each window to a one-row
+    // partition.
+    //
+    // Expected: `amount_reduce_created_at` (sum reducing by created_at)
+    // returns the per-status grand total across all months, not split per
+    // (status, month). Status totals from seed: completed=1400, pending=650,
+    // cancelled=200. With reduce_by working, every row for a given status
+    // shows the same total regardless of month.
+    let query = indoc! {r#"
+        measures:
+          - orders.amount_reduce_created_at
+        dimensions:
+          - orders.status
+        time_dimensions:
+          - dimension: orders.created_at
+            granularity: month
+            dateRange:
+              - "2024-01-01"
+              - "2024-03-31"
+        order:
+          - id: orders.status
+          - id: orders.created_at
+    "#};
+
+    ctx.build_sql(query).unwrap();
+
+    if let Some(result) = ctx.try_execute_pg(query, SEED).await {
+        insta::assert_snapshot!(result);
+    }
+}

rust/cube/cubesqlplanner/cubesqlplanner/src/tests/integration/multi_stage/snapshots/cubesqlplanner__tests__integration__multi_stage__group_by__group_by_time_dim_multiple_granularities.snap

@@ -0,0 +1,19 @@
+---
+source: cubesqlplanner/cubesqlplanner/src/tests/integration/multi_stage/group_by.rs
+assertion_line: 136
+expression: result
+---
+orders__created_at_month | orders__created_at_week | orders__amount_group_by_status_time
+-------------------------+-------------------------+------------------------------------
+2024-01-01 00:00:00      | 2024-01-01 00:00:00     | 500.00                             
+2024-01-01 00:00:00      | 2024-01-08 00:00:00     | 500.00                             
+2024-01-01 00:00:00      | 2024-01-15 00:00:00     | 500.00                             
+2024-01-01 00:00:00      | 2024-01-22 00:00:00     | 500.00                             
+2024-02-01 00:00:00      | 2024-01-29 00:00:00     | 750.00                             
+2024-02-01 00:00:00      | 2024-02-05 00:00:00     | 750.00                             
+2024-02-01 00:00:00      | 2024-02-12 00:00:00     | 750.00                             
+2024-02-01 00:00:00      | 2024-02-19 00:00:00     | 750.00                             
+2024-03-01 00:00:00      | 2024-02-26 00:00:00     | 1000.00                            
+2024-03-01 00:00:00      | 2024-03-04 00:00:00     | 1000.00                            
+2024-03-01 00:00:00      | 2024-03-11 00:00:00     | 1000.00                            
+2024-03-01 00:00:00      | 2024-03-18 00:00:00     | 1000.00

rust/cube/cubesqlplanner/cubesqlplanner/src/tests/integration/multi_stage/snapshots/cubesqlplanner__tests__integration__multi_stage__reduce_by__reduce_by_time_dim.snap

@@ -0,0 +1,15 @@
+---
+source: cubesqlplanner/src/tests/integration/multi_stage/reduce_by.rs
+expression: result
+---
+orders__status | orders__created_at_month | orders__amount_reduce_created_at
+---------------+--------------------------+---------------------------------
+cancelled      | 2024-01-01 00:00:00      | 200.00                          
+cancelled      | 2024-02-01 00:00:00      | 200.00                          
+cancelled      | 2024-03-01 00:00:00      | 200.00                          
+completed      | 2024-01-01 00:00:00      | 1400.00                         
+completed      | 2024-02-01 00:00:00      | 1400.00                         
+completed      | 2024-03-01 00:00:00      | 1400.00                         
+pending        | 2024-01-01 00:00:00      | 650.00                          
+pending        | 2024-02-01 00:00:00      | 650.00                          
+pending        | 2024-03-01 00:00:00      | 650.00