>> A .Net developer told me that the GUID should ideally be 32 characters.
He's likely referring to the UID version 4 format.
https://en.wikipedia.org/wiki/Universally_unique_identifierwhich is a 16 byte string (but often represented as 32 hex digits, with some colons.) (16 character alphabet, 0-9 and a-f)
These have about 121 bits of randomness (aka "entropy")
The Guids we tend to use in Clarion are also 16 chars long, but because it's easier to deal with text values, the alphabet is restricted to 36 characters (0-9 and A-Z). This results in approximately 83 bits of entropy.
So yes, a UIDv4 has more bits of entropy, and can hold more values than the Guid you are using. However it is harder to deal with as it can contain binary values, so needs to continually be encoded and decoded when moving to a text form.
The risk of a collision is n / 2^82 where n is the number of records in your table. (Not in the database, in the table.) If you feel that this value rises to unacceptably high levels then you can increase the length of the string, or the size of the alphabet. I would suggest this is a useful thing to do when you are expecting around 4 835 703 278 458 516 698 records - at which point the risk of a collision would be about 1 in a million.
Topic: GUID Question (Read 3195 times)