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Date: | Tue, 28 Nov 2006 23:40:31 EST |
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I had to go and do some research on TurboIMAGE again just to refresh my
memory before
I go throwing in my 0.5 cents worth on this topic --
Image detail sets:
There is no such thing as a "logical delete" or "logical delete flag."
When a program calls DBDELETE on a *detail* dataset the BACKWARD and FORWARD
entry pointers of the previous and next entry on the chain no longer point
to the DBDELETE'd detail entry. The DBDELETE'd entry is no longer accessible.
This DBDELETE'd entry then becomes part of the delete chain.
If the detail dataset employs sort keys then the updating of the backward
and forward pointers gets even nastier. TurboIMAGE effectively "breaks" the
chain to rebuild the
backward and forward entry pointers on the chain........
If you DBDELETE entries from a manual master dataset and said DBDELETE'd
entry is part of a synonym chain then that entry is supplanted with the next
entry on the synonym chain. For example, if there are 6 entries on a synonym
chain and you DBDELETE entry #3, then
entry #4 moves up to entry #3, entry #5 moves up to entry #4, entry #6 moves
up to entry #5.
Just my 0.5 cents worth of what I know of TurboIMAGE.
Brian Donaldson.
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