Time stamps and validity of a frame are usually set by the Calibration Time-stamp editor web service http://calts.astro-wise.orgCalTS, but they can also be changed at the awe-prompt. After changing these attributes the object can be commited to the database using the recommit method. Notice that only the timestamp_start, timestamp_end and is_valid (super flag) can be (re)commited to the database in this manner, any other attribute that is changed will not be updated in the database.
Python example:
WARNING: the recommit(s) have been commented out in this example, these will change the timestamps and is_valid of the BiasFrame in the database!!
# query for a BiasFrame
awe> qry = BiasFrame.instrument.name == 'WFI'
awe> bias = qry[0]
# substract one day from the timestamps start
awe> bias.timestamp_start -= datetime.timedelta(1)
# and set timestamp_end to far future
awe> bias.timestamp_end = datetime.datetime(2010, 1, 1)
# and commit changes to the database
awe> #bias.recommit()
# make the BiasFrame invalid
awe> bias.is_valid = 0
awe> #bias.recommit()
# make the BiasFrame valid again
awe> bias.is_valid = 1
awe> #bias.recommit()