Storage of Uvias IDs on OWOT
============================

All IDs must be 64 bit.
They must be in hexadecimal form.
They must not be padded by zeros at the beginning.
All characters in the IDs must be lower case.
All IDs must start with "x" (Code 120, 0x78). The reason being that it's required for the database to be 100% sure the ID is a string. Some hex strings can be all base-10 digits, and those would confuse the database. The letter "x" seems suitable because it's commonly used as the letter to escape hex sequences.

These mainly apply when referencing user ids in the database.
If a user is deleted and cannot be found in the Uvias database, OWOT will refer to the IDs as "uid~<ID>" (without quotes) on the website.
It follows the same rules as above, but without the letter "x" at the beginning.

Examples
========

References in database:
    x112210f4b2d230a2       (123456789101112131 decimal)
    x12d687                 (1234567 decimal)
    xffffffffffffff85       (-123 decimal)

When user is deleted (shown on website):
    uid~7fffffffffffffff        (9223372036854775807 decimal)
    uid~75bcd15                 (123456789 decimal)
    uid~ffffffffffffff9c        (-100 in deciamal)