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Different results with queries in labs versus production around september 21st.


The following query returns different (very different) results in production that it does in labs:

Production:
----------------
SELECT count(log_user)
   FROM enwiki.logging
        /* exclude proxy registrations */
  WHERE log_type = 'newusers'
        /* only include self-created users, exclude attached and proxy-registered users */
    AND log_action = 'create'
    AND log_timestamp BETWEEN 20140921000000 AND 20140922000000;

Returns: 8027


Labs:
--------
SELECT count(log_user)
   FROM logging
        /* exclude proxy registrations */
  WHERE log_type = 'newusers'
        /* only include self-created users, exclude attached and proxy-registered users */
    AND log_action = 'create'
    AND log_timestamp BETWEEN 20140921000000 AND 20140922000000;

Returns: 6842



Halfak did some digging and placed the missing rows in 

analytics-store:staging.missing_labs_new_user_20140921

It looks like there's 5 hours of the day where the rows were missing. 

mysql:research@analytics-store.eqiad.wmnet [staging]> select LEFT(log_timestamp, 10) as hour, count(*) from missing_labs_new_user_20140921 GROUP BY 1;
+------------+----------+
| hour       | count(*) |
+------------+----------+
| 2014092108 |       83 |
| 2014092109 |      336 |
| 2014092110 |      304 |
| 2014092111 |      344 |
| 2014092112 |      118 |
+------------+----------+
5 rows in set (0.01 sec)