How to form an APATID

WHY: This unique identifier reduces the chance of a single person being issued more than one library card. The Unique ID is a code, developed through a formula that combines patron name and birth date, which gives the patron record a unique identifier. There is a variable length field for Unique ID in the Sierra patron record.

HOW: Unique ID= the first 4 letters of patron’s last name + first letter of the patron’s first name + 1 character birth month and 2 numbers for the day. This is written in ALL CAPS.


Use only a single letter or number to indicate birth month, as follows:

  • January = 1
  • February = 2
  • March = 3
  • April = 4
  • May = 5
  • June = 6
  • July = 7
  • August = 8
  • September = 9
  • October = O
  • November = N
  • December = D

Example from above screen shot: Duck, Rosie, May 15 – DUCKR515

  • If last name is not long enough, use *, e.g., Elizabeth Lee Jan 15 LEE*E115

 Sierra will let you know if the Unique ID you are putting in the record has already been used. If you get this message, it may mean that the patron already has another card. You can use Unique ID as an index for searching in Sierra.

There is a smaller chance that the unique identifier has been used to indicate another patron. Sierra will let you know when this happens by displaying the record where the duplication exists. Take the time to verify that you are not reentering the same patron. If your patron is unique to our database, select override and continue the patron entry.