execStats in system.profile reports winning plan and rejected plans

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      db.setProfilingLevel(0);
db.system.profile.drop();
db.c.drop();
db.c.ensureIndex({a: 1});
db.c.ensureIndex({b: 1});
db.c.insert({a: 1, b: 1});
db.setProfilingLevel(2);
db.c.find({a: 1, b: 1}).itcount();
db.setProfilingLevel(2);
db.system.profile.find().pretty();
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      db.setProfilingLevel(0); db.system.profile.drop(); db.c.drop(); db.c.ensureIndex({a: 1}); db.c.ensureIndex({b: 1}); db.c.insert({a: 1, b: 1}); db.setProfilingLevel(2); db.c.find({a: 1, b: 1}).itcount(); db.setProfilingLevel(2); db.system.profile.find().pretty();
    • Query 10 (02/22/16), Query 11 (03/14/16)
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      When profiling is enabled, find operations will add a field called execStats containing some information about the execution of the query plan. In 2.6.x and 3.0.x versions, this contained information about the winning plan only. If the query used the multiplan path, information about the rejected plans was rejected.

      This behavior changed in 3.2.0 as a result of 5aefcdd under SERVER-20111. The profile entries now can contain execStats with a MULTI_PLAN stage. All children of the MULTI_PLAN stage are reported, regardless of which child represents the winning plan.

            Assignee:
            James Wahlin
            Reporter:
            David Storch
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              Created:
              Updated:
              Resolved: