GUID as other disadvantage, it is big, it's a data of it's own and indexing is not sequenced compare to SYS(2015).

If you open a SCX and VCX that's what VFP itself uses for PK




>>Can anybody certify that the SYS(2015) function is generating unique ID. I plan to use this as a primary key in a big system and I want to be sure it won't generate duplicate...
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>At least, I never heard of anybody trying to use it as a PK.
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>Let's see some solutions other people use for PKs.
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>How big is your system? If there are several computers connected over a single network, you might consider storing the next PK value in a table. (Integer; 4 bytes.)
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>For disconnected systems, some people use GUID. This one is guaranteed to be unique for machines that have network cards, and very unlikely to have duplicates for those that don't. (16 bytes.)
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>Another option is to assign an ID to each user (machine), and combine it with the first solution I presented. (6 bytes, if you use bintoc(User_id, 2) + bintoc(serialnumber(...))).
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>HTH,
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>Hilmar.