I have lately migrate my JIRA database from mysql to oracle,
my problem is the field “created” exists in the jiraissue and changegroup tables,on this field I effectuate many calculation but I was surprised by the difference of the format of the fields.
in mysql database the field creation has the type timeStamp so it has the follwing format:

and in Oracle database it has the type date and the format like the following:

How can I resolve this problem?
The format of your displayed Oracle DATE column is due to your IDE that you are viewing it through.
Oracle stores all portions of a date, to display the full date stored use this:
This will show you the full date that has been stored including the time portion. To store timestamps you need the column to be designated as a timestamp datatype column.
Ollie.
EDIT: You could change the NLS Date Format of your IDE to always show the full date format in it’s settings somewhere.