ContextQMD
Back to Mongo

Explain

jstests/query_golden/expected_output/explain.md

3.6.17-windows-splunk-v36.8 KB
Original Source

1. Test getting rejected plan out of explain

Cheapest plan (no ALL plans enum)

usedJoinOptimization: true

Winning plan

NESTED_LOOP_JOIN_EMBEDDING [a2.a = a,a = a,a1.a = a]
leftEmbeddingField: "none"
rightEmbeddingField: "a3"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  NESTED_LOOP_JOIN_EMBEDDING [a1.a = a,a = a]
  leftEmbeddingField: "none"
  rightEmbeddingField: "a2"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  NESTED_LOOP_JOIN_EMBEDDING [a = a]
  leftEmbeddingField: "none"
  rightEmbeddingField: "a1"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  COLLSCAN [test.explain_md]
  direction: "forward"

Rejected plans (total: 1)

HASH_JOIN_EMBEDDING [a2.a = a,a = a,a1.a = a]
leftEmbeddingField: "none"
rightEmbeddingField: "a3"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  NESTED_LOOP_JOIN_EMBEDDING [a1.a = a,a = a]
  leftEmbeddingField: "none"
  rightEmbeddingField: "a2"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  NESTED_LOOP_JOIN_EMBEDDING [a = a]
  leftEmbeddingField: "none"
  rightEmbeddingField: "a1"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  COLLSCAN [test.explain_md]
  direction: "forward"

ALL plans, subset level 0 only

usedJoinOptimization: true

Rejected plans (total: 1)

HASH_JOIN_EMBEDDING [a2.a = a,a = a,a1.a = a]
leftEmbeddingField: "none"
rightEmbeddingField: "a3"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  NESTED_LOOP_JOIN_EMBEDDING [a1.a = a,a = a]
  leftEmbeddingField: "none"
  rightEmbeddingField: "a2"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  NESTED_LOOP_JOIN_EMBEDDING [a = a]
  leftEmbeddingField: "none"
  rightEmbeddingField: "a1"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  COLLSCAN [test.explain_md]
  direction: "forward"

ALL plans, subset level 1 only

usedJoinOptimization: true

Rejected plans (total: 1)

HASH_JOIN_EMBEDDING [a2.a = a,a = a,a1.a = a]
leftEmbeddingField: "none"
rightEmbeddingField: "a3"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  NESTED_LOOP_JOIN_EMBEDDING [a1.a = a,a = a]
  leftEmbeddingField: "none"
  rightEmbeddingField: "a2"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  NESTED_LOOP_JOIN_EMBEDDING [a = a]
  leftEmbeddingField: "none"
  rightEmbeddingField: "a1"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  COLLSCAN [test.explain_md]
  direction: "forward"

ALL plans, subset level 2 only

usedJoinOptimization: true

Rejected plans (total: 1)

HASH_JOIN_EMBEDDING [a2.a = a,a = a,a1.a = a]
leftEmbeddingField: "none"
rightEmbeddingField: "a3"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  NESTED_LOOP_JOIN_EMBEDDING [a1.a = a,a = a]
  leftEmbeddingField: "none"
  rightEmbeddingField: "a2"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  NESTED_LOOP_JOIN_EMBEDDING [a = a]
  leftEmbeddingField: "none"
  rightEmbeddingField: "a1"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  COLLSCAN [test.explain_md]
  direction: "forward"

ALL plans, subset level 3 only

usedJoinOptimization: true

Rejected plans (total: 23)

Too many plans, printing only top 3 by cost.

NESTED_LOOP_JOIN_EMBEDDING [a1.a = a,a3.a = a,a = a]
leftEmbeddingField: "none"
rightEmbeddingField: "a2"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  NESTED_LOOP_JOIN_EMBEDDING [a = a,a1.a = a]
  leftEmbeddingField: "none"
  rightEmbeddingField: "a3"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  NESTED_LOOP_JOIN_EMBEDDING [a = a]
  leftEmbeddingField: "none"
  rightEmbeddingField: "a1"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  COLLSCAN [test.explain_md]
  direction: "forward"

NESTED_LOOP_JOIN_EMBEDDING [a = a,a2.a = a,a3.a = a]
leftEmbeddingField: "none"
rightEmbeddingField: "a1"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  NESTED_LOOP_JOIN_EMBEDDING [a2.a = a,a = a]
  leftEmbeddingField: "none"
  rightEmbeddingField: "a3"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  NESTED_LOOP_JOIN_EMBEDDING [a = a]
  leftEmbeddingField: "none"
  rightEmbeddingField: "a2"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  COLLSCAN [test.explain_md]
  direction: "forward"

NESTED_LOOP_JOIN_EMBEDDING [a1.a = a,a2.a = a,a3.a = a]
leftEmbeddingField: "none"
rightEmbeddingField: "none"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  NESTED_LOOP_JOIN_EMBEDDING [a2.a = a,a1.a = a]
  leftEmbeddingField: "none"
  rightEmbeddingField: "a3"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  NESTED_LOOP_JOIN_EMBEDDING [a = a]
  leftEmbeddingField: "a1"
  rightEmbeddingField: "a2"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  COLLSCAN [test.explain_md]
  direction: "forward"

ALL plans, all levels

usedJoinOptimization: true

Rejected plans (total: 431)

Too many plans, printing only top 3 by cost.

NESTED_LOOP_JOIN_EMBEDDING [a2.a = a,a = a,a1.a = a]
leftEmbeddingField: "none"
rightEmbeddingField: "a3"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  NESTED_LOOP_JOIN_EMBEDDING [a1.a = a,a = a]
  leftEmbeddingField: "none"
  rightEmbeddingField: "a2"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  NESTED_LOOP_JOIN_EMBEDDING [a = a]
  leftEmbeddingField: "a1"
  rightEmbeddingField: "none"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  COLLSCAN [test.explain_md]
  direction: "forward"

NESTED_LOOP_JOIN_EMBEDDING [a2.a = a,a = a,a1.a = a]
leftEmbeddingField: "none"
rightEmbeddingField: "a3"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  NESTED_LOOP_JOIN_EMBEDDING [a = a,a2.a = a]
  leftEmbeddingField: "none"
  rightEmbeddingField: "a1"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  NESTED_LOOP_JOIN_EMBEDDING [a = a]
  leftEmbeddingField: "none"
  rightEmbeddingField: "a2"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  COLLSCAN [test.explain_md]
  direction: "forward"

NESTED_LOOP_JOIN_EMBEDDING [a2.a = a,a = a,a1.a = a]
leftEmbeddingField: "none"
rightEmbeddingField: "a3"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  NESTED_LOOP_JOIN_EMBEDDING [a = a,a2.a = a]
  leftEmbeddingField: "none"
  rightEmbeddingField: "a1"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  NESTED_LOOP_JOIN_EMBEDDING [a = a]
  leftEmbeddingField: "a2"
  rightEmbeddingField: "none"
  |  |
  |  COLLSCAN [test.explain_md]
  |  direction: "forward"
  |
  COLLSCAN [test.explain_md]
  direction: "forward"