LF question

I have a LF built over a DDL-Table. The DDL table is defined without a key
[Arrival].

The LF has an Item Number field defined as Unique.

When I compile the LF, the LF allows all operations except a Write
operation.

Does anyone know where it is documented what causes this? It's not the
first time I have seen it. Why would you not be able to add records to a
LF that would be written to its PF? I have no idea if the Unique key on
the LF causes this but wanted to include it in case.

Thank you,

Doug



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