As documented in https://meta.wikimedia.org/wiki/Schema:EventCapsule , EventLogging tables are currently using timestamps in the YYYYMMDDHHMMSSformat.
However, it appears that the new Hadoop-based EL tables in Hive uses Epoch timestamps instead, at least the one that is being generated via this pilot process T177783: Eventlogging refine popups, temporary cron.
(On the other hand, those EL tables on Hive that were imported from MySQL with Sqoop appear to still use YYYYMMDDHHMMSS, see e.g. the example query at T172322#3551131 .)
I can probably live with this in the present example (tbayer.popups). But in general this will break a great many existing queries. Of course using Epoch has advantages too (e.g. calculating relative time differences becomes much easier), and hopefully the new processes will consistently add partitions for year, month, day and hour, so that these can be used for restricting queries to certain timespans instead. But it still increases the switching costs a lot, so there needs to be an informed decision about this if this in case Epoch is chosen for the general approach.
SELECT MIN(timestamp) FROM tbayer.popups WHERE year = 2017 AND month = 10 AND day = 31 AND hour = 0; _c0 1509408000 1 row selected (32.214 seconds)