Contents Index The AUTOINCREMENT default The NULL default

ASA SQL User's Guide
  Ensuring Data Integrity
    Using column defaults

The NEWID default


UUIDs (Universally Unique IDentifiers), also known as GUIDs (Globally Unique IDentifiers), can be used to uniquely identify rows in a table. The values are generated such that a value produced on one computer will not match that produced on another. They can therefore be used as keys in replication and synchronization environments.

Using UUID values as primary keys has some tradeoffs when you compare them with using GLOBAL AUTOINCREMENT values. For example,

For more information, see the NEWID function [Miscellaneous] , the STRTOUUID function [STRING] , the UUIDTOSTR function [STRING] , or the UNIQUEIDENTIFIER data type [Binary].


Contents Index The AUTOINCREMENT default The NULL default