Database Management
Reference Manual
Introduction to Database Concepts
:
Database Elements
: Reference Number
Reference Number
Every element has a reference number, which is assigned when the element is created, and is unique to that element within the project. The reference number comprises two 32 bit integers. This is displayed in the form:
=1234/6789
The first integer is composed from the database number and a bucket number. The bucket number allows for multiple users to access a database simultaneously without the risk of generating the same reference number; bucket numbers are allocated to users on a temporary bases starting at 1. In single write databases, the bucket number is always 1.
The second integer is a sequence number, starting at 0, and incrementing each time an element is created within that database and bucket.
The algorithm for allocating a reference number is:
1st part - DB number plus (bucket number * 8192)
2nd part - Increment starting from 0.
Thus, for example, for DB 1, the first element created will have a reference number of =8193/0 (this will be the world element since this is always created first).
The reference number is never changed once an element has been created.
1974 to current year.
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