query: SELECT
  '2009-03-20 11:30:01',
  unix_timestamp('2009-03-20 11:30:01')
FROM src LIMIT 1
Input: default/src
Output: /data/users/athusoo/commits/hive_trunk_ws8/ql/../build/ql/tmp/1312227505/619820167.10000
2009-03-20 11:30:01	1237573801
query: SELECT
  '2009-03-20',
  unix_timestamp('2009-03-20', 'yyyy-MM-dd')
FROM src LIMIT 1
Input: default/src
Output: /data/users/athusoo/commits/hive_trunk_ws8/ql/../build/ql/tmp/24449050/574490019.10000
2009-03-20	1237532400
query: SELECT
  '2009 Mar 20 11:30:01 am',
  unix_timestamp('2009 Mar 20 11:30:01 am', 'yyyy MMM dd h:mm:ss a')
FROM src LIMIT 1
Input: default/src
Output: /data/users/athusoo/commits/hive_trunk_ws8/ql/../build/ql/tmp/113858045/511496819.10000
2009 Mar 20 11:30:01 am	1237573801
query: SELECT
  'random_string',
  unix_timestamp('random_string')
FROM src LIMIT 1
Input: default/src
Output: /data/users/athusoo/commits/hive_trunk_ws8/ql/../build/ql/tmp/7890380/263814004.10000
random_string	NULL