eds record numbers - Ping Rob

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In database.htm, you write:

> You can also access records directly, with no search, if you know the
> current record number within the table. Record numbers are from 1 to
> the length (current number of records), of the table.=20

I feel it would be instructive to note that record numbers are
"fluid"; for example if you insert a record with key "2", it is
naturally given record number 1. However, if you subsequently insert a
record with key "1", then the record number of the newly inserted
record is 1, and the first record now has record number 2.

The most important point, as I just found out, is you cannot use the
record number with any kind of persistence; obviously not storing it
permanently on the data file, but critically not in a temporary local
variable either.

It also took me a while to realise that read next by key value is just
get record number+1.

Also, (again, just a documentation issue), db_find_key returns a
negative key. It would be useful to include an example of partial key
read using this technique.

Lastly, In db_find_key you also write:
> You can select a range of records by searching for the first and last
> key values in the range. If those key values don't exist you'll get a
> negative value showing where they would be if they existed.=20
Specifically, "can select a range" threw me, I think, well I'm lost
anyway - can you explain this point further?

Pete
Something to keep you occupied waiting for bug reports on 2.4 smile

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