UUID Question

[Greg Hines]

Hi Everyone,

I want to add a UUID as the PK to my database and I've noticed that several of the characters repeat themselves in each UUID. eg:

mysql> select uuid();
+--------------------------------------+
| uuid() |
+--------------------------------------+
| 4de854ae-2b06-11df-b0da-ca39c11a3feb |
+--------------------------------------+
1 row in set

mysql> select uuid();
+--------------------------------------+
| uuid() |
+--------------------------------------+
| 4e5d8291-2b06-11df-b0da-ca39c11a3feb |
+--------------------------------------+
1 row in set

mysql> select uuid();
+--------------------------------------+
| uuid() |
+--------------------------------------+
| 4f58d4ea-2b06-11df-b0da-ca39c11a3feb |
+--------------------------------------+
1 row in set

mysql> select uuid();
+--------------------------------------+
| uuid() |
+--------------------------------------+
| 4f9bf4d9-2b06-11df-b0da-ca39c11a3feb |
+--------------------------------------+
1 row in set

2b06-11df-b0da-ca39c11a3feb is in every UUID. Just seems a waste to have a varchar(36) field when a varchar(8) would do the trick.

Can anyone explain this behaviour to me as I would not have expected the repeating of all these characters in the UUID?

TIA

Greg