Unexpected results from SQL query with BETWEEN timestamps

Question

I have created a little test app to track down a problem I experienced with Postgres on Heroku: http://snippi.com/s/xd511rf

As you can see in line 49, I

Answer 1

Check the data type of the columns and your time zone. You may be confusing timestamp with time zone and timestamp.

Looks like you have timestamp in your table, but query with timestamptz. This way, it all depends on the local time zone of your session (which defaults to the time zone of the server if not specified otherwise.)

Switch both to timestamptz, or timestamp if time zones are completely irrelevant to you. (If in doubt, use timestamptz.)

Not the cause of your problem, but your query should probably be:

SELECT id, text, category, starttime, endtime, creation 
FROM   entries 
WHERE  starttime >= timestamp '2013-03-21' -- defaults to 00:00 time
AND    starttime <  timestamp '2013-03-22'
ORDER  BY id

a BETWEEN x AND y is almost always wrong for timestamp types due to fractional numbers! What would your query do with starttime = '2013-03-21T23:59:59.123+00'?