Graph:
BASE -- F1 -- F2
Solution with seed 0:
NESTED_LOOP_JOIN
---leftEmbeddingField: (none)
---rightEmbeddingField: (none)
---joinPredicates:
------f1.a = a
---Outer:
------NESTED_LOOP_JOIN
---------leftEmbeddingField: f2
---------rightEmbeddingField: f1
---------joinPredicates:
------------c = c
---------Outer:
------------COLLSCAN
---------------ns = test.f2
---------------filter = $and
---------------nodeId = 1
---------------fetched = 1
---------------sortedByDiskLoc = 0
---------------providedSorts = {baseSortPattern: {}, ignoredFields: []}
---------Inner:
------------COLLSCAN
---------------ns = test.f1
---------------filter = $and
---------------nodeId = 2
---------------fetched = 1
---------------sortedByDiskLoc = 0
---------------providedSorts = {baseSortPattern: {}, ignoredFields: []}
---Inner:
------COLLSCAN
---------ns = test.base
---------filter = $and
---------nodeId = 4
---------fetched = 1
---------sortedByDiskLoc = 0
---------providedSorts = {baseSortPattern: {}, ignoredFields: []}

Solution with seed 4:
NESTED_LOOP_JOIN
---leftEmbeddingField: (none)
---rightEmbeddingField: (none)
---joinPredicates:
------f1.a = a
---Outer:
------NESTED_LOOP_JOIN
---------leftEmbeddingField: f1
---------rightEmbeddingField: f2
---------joinPredicates:
------------c = c
---------Outer:
------------COLLSCAN
---------------ns = test.f1
---------------filter = $and
---------------nodeId = 1
---------------fetched = 1
---------------sortedByDiskLoc = 0
---------------providedSorts = {baseSortPattern: {}, ignoredFields: []}
---------Inner:
------------COLLSCAN
---------------ns = test.f2
---------------filter = $and
---------------nodeId = 2
---------------fetched = 1
---------------sortedByDiskLoc = 0
---------------providedSorts = {baseSortPattern: {}, ignoredFields: []}
---Inner:
------COLLSCAN
---------ns = test.base
---------filter = $and
---------nodeId = 4
---------fetched = 1
---------sortedByDiskLoc = 0
---------providedSorts = {baseSortPattern: {}, ignoredFields: []}

