Auto Increment Field in Django/Python
Instead of deleting orders - you should create a field which is a boolean (call it whatever you like - for example, deleted) and set this field to 1 for "deleted" orders.
Messing with a serial field (which is what your auto-increment field is called in postgres) will lead to problems later; especially if you have foreign keys and relationships with tables.
Not only will it impact your database server's performance; it also will impact on your business as eventually you will have two orders floating around that have the same order number; even though you have "deleted" one from the database, the order number may already be referenced somewhere else - like in a receipt your printed for your customer.
I have a table in a django app where one of the fields is called Order (as in sort order) and is an integer. Every time a new record is entered the field auto increments itself to the next number. My issue is when a record is deleted I would like the other records to shift a number up and cant find anything that would recalculate all the records in the table and shift them a number up if a record is deleted. 
For instance there are 5 records in the table where order numbers are 1, 2, 3, 4, and 5. Someone deleted record number 2 and now I would like numbers 3, 4, and 5 to move up to take the deleted number 2's place so the order numbers would now be 1, 2, 3, and 4. Is it possible with python, postgres and django?
Thanks in Advance!