Dedupe qualified name for GroupByMetricSpecs (#1171)

Typically, a spec's qualified name is `<entity_links>__<element_name>`.
In the case of `GroupByMetricSpecs`, this name isn't guaranteed to be
unique. That's because the `metric_subquery_entity_links` are not
accounted for. This will also be a problem in SQL generation, since you
could end up with a query that references two different group by metrics
by the same column name. To avoid that, here I added some deduping logic
for the qualified name.
1. If `entity_links` matches `metric_subquery_entity_links`, use the
standard qualified name.
2. If they don't match, include both, e.g.,
`<entity_links>__<metric_subquery_entity_links>__<element_name>`. You
can still tell where one path ends and the next begins because they will
both end with the same entity link, which is the last link before the
element name.

metricflow-semantics/metricflow_semantics/specs/dunder_column_association_resolver.py

@@ -1,7 +1,7 @@
 from __future__ import annotations
 
 from metricflow_semantics.model.semantic_manifest_lookup import SemanticManifestLookup
-from metricflow_semantics.naming.linkable_spec_name import DUNDER, StructuredLinkableSpecName
+from metricflow_semantics.naming.linkable_spec_name import DUNDER
 from metricflow_semantics.specs.column_assoc import (
     ColumnAssociation,
     ColumnAssociationResolver,
@@ -59,23 +59,13 @@ def visit_measure_spec(self, measure_spec: MeasureSpec) -> ColumnAssociation:  #
 
     def visit_dimension_spec(self, dimension_spec: DimensionSpec) -> ColumnAssociation:  # noqa: D102
         return ColumnAssociation(
-            column_name=StructuredLinkableSpecName(
-                entity_link_names=tuple(x.element_name for x in dimension_spec.entity_links),
-                element_name=dimension_spec.element_name,
-            ).qualified_name,
+            column_name=dimension_spec.qualified_name,
             single_column_correlation_key=SingleColumnCorrelationKey(),
         )
 
     def visit_time_dimension_spec(self, time_dimension_spec: TimeDimensionSpec) -> ColumnAssociation:  # noqa: D102
-        column_name = StructuredLinkableSpecName(
-            entity_link_names=tuple(x.element_name for x in time_dimension_spec.entity_links),
-            element_name=time_dimension_spec.element_name,
-            time_granularity=time_dimension_spec.time_granularity,
-            date_part=time_dimension_spec.date_part,
-        ).qualified_name
-
         return ColumnAssociation(
-            column_name=column_name
+            column_name=time_dimension_spec.qualified_name
             + (
                 f"{DUNDER}{time_dimension_spec.aggregation_state.value.lower()}"
                 if time_dimension_spec.aggregation_state
@@ -86,19 +76,13 @@ def visit_time_dimension_spec(self, time_dimension_spec: TimeDimensionSpec) -> C
 
     def visit_entity_spec(self, entity_spec: EntitySpec) -> ColumnAssociation:  # noqa: D102
         return ColumnAssociation(
-            column_name=StructuredLinkableSpecName(
-                entity_link_names=tuple(x.element_name for x in entity_spec.entity_links),
-                element_name=entity_spec.element_name,
-            ).qualified_name,
+            column_name=entity_spec.qualified_name,
             single_column_correlation_key=SingleColumnCorrelationKey(),
         )
 
     def visit_group_by_metric_spec(self, group_by_metric_spec: GroupByMetricSpec) -> ColumnAssociation:  # noqa: D102
         return ColumnAssociation(
-            column_name=StructuredLinkableSpecName(
-                entity_link_names=tuple(x.element_name for x in group_by_metric_spec.entity_links),
-                element_name=group_by_metric_spec.element_name,
-            ).qualified_name,
+            column_name=group_by_metric_spec.qualified_name,
             single_column_correlation_key=SingleColumnCorrelationKey(),
         )
 

metricflow-semantics/metricflow_semantics/specs/spec_classes.py

@@ -755,6 +755,23 @@ def metric_subquery_entity_spec(self) -> EntitySpec:
             entity_links=self.metric_subquery_entity_links[:-1],
         )
 
+    @property
+    def qualified_name(self) -> str:
+        """Element name prefixed with entity links.
+
+        If same entity links are used in inner & outer query, use standard qualified name (country__bookings).
+        Else, specify both sets of entity links (listing__country__user__country__bookings).
+        """
+        if self.entity_links == self.metric_subquery_entity_links:
+            entity_links = self.entity_links
+        else:
+            entity_links = self.entity_links + self.metric_subquery_entity_links
+
+        return StructuredLinkableSpecName(
+            entity_link_names=tuple(entity_link.element_name for entity_link in entity_links),
+            element_name=self.element_name,
+        ).qualified_name
+
     def __eq__(self, other: Any) -> bool:  # type: ignore[misc] # noqa: D105
         if not isinstance(other, GroupByMetricSpec):
             return False