maybe

tests/trace_server/test_calls_query_builder.py

@@ -11,15 +11,14 @@ def assert_sql(cq: CallsQuery, exp_queries, exp_params):
     queries = cq.as_sql(pb)
     params = pb.get_params()
 
-    assert exp_params == params
-    assert len(queries) == len(exp_queries)
-
     for qr, qe in zip(queries, exp_queries):
         exp_formatted = sqlparse.format(qe, reindent=True)
         found_formatted = sqlparse.format(qr, reindent=True)
 
         assert exp_formatted == found_formatted
 
+    assert exp_params == params
+
 
 def test_query_baseline() -> None:
     cq = CallsQuery(project_id="project")

weave/trace_server/calls_query_builder.py

@@ -464,10 +464,10 @@ def as_sql(self, pb: ParamBuilder, table_alias: str = "calls_merged") -> list[st
             )
         )
 
-        should_optimize = (
+        should_optimize = self.should_do_two_step_query() or (
             has_heavy_fields and do_predicate_pushdown
-        ) or self.include_costs
-        if not should_optimize:
+        )
+        if not should_optimize and not self.include_costs:
             return [self._as_sql_base_format(pb, table_alias)]
 
         # Build the two queries