Fix/speedup for scheduling scope (#10341)

* LATERAL to reduce calculated descendants

The descendants are calculated to know when to stop calculating successors as they are (transitively) scheduled manually.

* linting

app/models/work_packages/scopes/for_scheduling.rb

@@ -119,51 +119,52 @@ module WorkPackages::Scopes
       def paths_sql(work_packages)
         values = work_packages.map { |wp| "(#{wp.id}, false)" }.join(', ')
 
-        <<~SQL
-             to_schedule (id, manually) AS (
-               SELECT * FROM (VALUES#{values}) AS t(id, manually)
+        <<~SQL.squish
+          to_schedule (id, manually) AS (
+            SELECT * FROM (VALUES#{values}) AS t(id, manually)
 
-               UNION
+            UNION
 
-               SELECT
-                 CASE
-                   WHEN relations.to_id = to_schedule.id
-                   THEN relations.from_id
-                   ELSE relations.to_id
-                 END id,
-                 (work_packages.schedule_manually OR COALESCE(descendants.schedule_manually, false)) manually
-               FROM
-                 to_schedule
-               JOIN
-                 relations
-                 ON NOT to_schedule.manually
-                 AND (#{relations_condition_sql})
-                 AND
-                   ((relations.to_id = to_schedule.id)
-                   OR (relations.from_id = to_schedule.id AND relations.follows = 0))
-               LEFT JOIN work_packages
-                 ON (CASE
-                   WHEN relations.to_id = to_schedule.id
-                   THEN relations.from_id
-                   ELSE relations.to_id
-                   END) = work_packages.id
-               LEFT JOIN (
-                 SELECT
-                   relations.from_id,
-                   bool_and(COALESCE(work_packages.schedule_manually, false)) schedule_manually
-                 FROM relations relations
-                 JOIN work_packages
-                 ON
-                   work_packages.id = relations.to_id
-                   AND relations.follows = 0 AND #{relations_condition_sql(transitive: true)}
-                 GROUP BY relations.from_id
-          ) descendants ON work_packages.id = descendants.from_id
-             )
+            SELECT
+              CASE
+                WHEN relations.to_id = to_schedule.id
+                THEN relations.from_id
+                ELSE relations.to_id
+              END id,
+              (related_work_packages.schedule_manually OR COALESCE(descendants.schedule_manually, false)) manually
+            FROM
+              to_schedule
+            JOIN
+              relations
+              ON NOT to_schedule.manually
+              AND (#{relations_condition_sql})
+              AND
+                ((relations.to_id = to_schedule.id)
+                OR (relations.from_id = to_schedule.id AND relations.follows = 0))
+            LEFT JOIN work_packages related_work_packages
+              ON (CASE
+                WHEN relations.to_id = to_schedule.id
+                THEN relations.from_id
+                ELSE relations.to_id
+                END) = related_work_packages.id
+            LEFT JOIN LATERAL (
+              SELECT
+                relations.from_id,
+                bool_and(COALESCE(work_packages.schedule_manually, false)) schedule_manually
+              FROM relations relations
+              JOIN work_packages
+              ON
+                work_packages.id = relations.to_id
+                AND related_work_packages.id = relations.from_id
+                AND relations.follows = 0 AND #{relations_condition_sql(transitive: true)}
+              GROUP BY relations.from_id
+            ) descendants ON related_work_packages.id = descendants.from_id
+          )
         SQL
       end
 
       def relations_condition_sql(transitive: false)
-        <<~SQL
+        <<~SQL.squish
           "relations"."relates" = 0 AND "relations"."duplicates" = 0 AND "relations"."blocks" = 0 AND "relations"."includes" = 0 AND "relations"."requires" = 0
             AND (relations.hierarchy + relations.relates + relations.duplicates + relations.follows + relations.blocks + relations.includes + relations.requires #{transitive ? '>' : ''}= 1)
         SQL