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UUID (aka GUID) vs. Oracle sequence number

When you want to generate a unique number, for a primary key, the most common idea (and the right one) is to get a number from an always increasing generator. Oracle provides SEQUENCE for this purpose, which is optimized, easy to use and scalable.

But some application developer has the idea to use a UUID (Universally Unique Identifier) also known as GUID (Globally Unique Identifier). The main advantage is that you do not need a shared object like a sequence because there is no need for a central authority. UUID is generated with a hash function on some local identifiers (host, process, thread) and the hash value is large enough to reduce the probability of collisions without the need for a shared central authority.

However, in the context of Oracle Database: