Hello mguo,

I don't know the straight answer, but we can play among the possibilities.

Suppose Data Manager uses an auto-incremental variable, stored in a palmOS db 
(e.g.), to assign an uniqueID to a new record.

Since it is auto-incremental, it is always a new value (for uniqueIDs), and no 
check for an existing uniqueID would be needed BUT... "it is always a new 
value" is a wrong sentence, since you can assign an arbitrary uniqueID to your 
record with DmSetRecordInfo() (It is not recommended, but you can.). So, Data 
Manager needs to check if the new value is an existing uniqueID.

Another issue is: what happens when that auto-incremental variable overflows 
the UInt32 limit? It's a long value, but it's possible. For example, some 
softwares may need to create and delete records very frequently... so that 
variable would reset and Data Manager would re-use non-used uniqueIDs (from 
deleted records).

Thus, somewhere in time, Data Manager must re-use uniqueIDs, either by using an 
auto-incremental variable, either by searching for the first non-used uniqueID. 
That is, my answer is "the uniqueIDs are re-usable". But I just don't know the 
exact answer.

I hope these words help you a little.

(Sorry for my English errors.)
Sony Santos
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