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  1. Core Server
  2. SERVER-19679

Presence of pipe '|' is search causes all keys to be examined

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    • Type: Icon: Bug Bug
    • Resolution: Duplicate
    • Priority: Icon: Major - P3 Major - P3
    • None
    • Affects Version/s: 3.0.4
    • Component/s: Querying
    • None
    • Fully Compatible
    • ALL
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      1. setup system with 3.0.4
        1. mongo shell
        2. import enclosed dump file
        3. run "db.re.find({_id:/^\Q1234^mr^sjc|ENT\E/}).explain('executionStats')"
        4. check the "totalKeysExamined" field in output, should be 2 but is 9
        5. run "db.re.find({_id:/^\Q1234^mr^sjc\E/}).explain('executionStats')"
        6. check the "totalKeysExamined" field in output
      2. setup system with 2.6.9
        1. mongo shell
        2. import enclosed dump file
        3. run "db.re.find({_id:/^\Q1234^mr^sjc|ENT\E/}).explain('executionStats')"
        4. check the "nscanned" field in output, should be 2 but is 9
        5. run "db.re.find({_id:/^\Q1234^mr^sjc\E/}).explain('executionStats')"
        6. check the "nscanned" field in output
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      setup system with 3.0.4 mongo shell import enclosed dump file run "db.re.find({_id:/^\Q1234^mr^sjc|ENT\E/}).explain('executionStats')" check the "totalKeysExamined" field in output, should be 2 but is 9 run "db.re.find({_id:/^\Q1234^mr^sjc\E/}).explain('executionStats')" check the "totalKeysExamined" field in output setup system with 2.6.9 mongo shell import enclosed dump file run "db.re.find({_id:/^\Q1234^mr^sjc|ENT\E/}).explain('executionStats')" check the "nscanned" field in output, should be 2 but is 9 run "db.re.find({_id:/^\Q1234^mr^sjc\E/}).explain('executionStats')" check the "nscanned" field in output

      There appears to be a regression with how the query processor handles the pipe character '|'. In version 3.0.4, regular queries using the pipe character scan all entries in the index. In version 2.6.9, regular queries using the pipe character DO NOT scan all entries in the index.

        1. test_regexp-data.dump
          0.8 kB
          Steven Hand

            Assignee:
            Unassigned Unassigned
            Reporter:
            steven.hand Steven Hand
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              Created:
              Updated:
              Resolved: