Re: ADO Bookmark status

Stephen Howe wrote:
I'm not. I can't think of any situation where the bookmark would no
longer point at a record, if that record still existed in the
recordset. Is that what you mean by "invalid"? That it no longer
points at a record?

Server-sided ForwardOnly recordsets.
If ADO permitted a bookmark, you then read another 1024 records,
returning back to the record would be a problem if it is no longer in
the cache.

I dismissed this situation because I've yet to come across a provider that
supports bookmarks for this cursor type (dynamic cursors also lack bookmark
support - only cursors whose membership is fixed can support bookmarks.).

It is after all the _DATABASE_ cursor that is determining access to
records here.
I would imagine that ADO _could_ permit returning to a record if you
had shot past it, but it was still in the cache.
No idea if it does this.

It does. By default, the cache-size is one record, but there is nothing
preventing you from setting it higher, in which case navigation back to
those records in cache will be supported. However, bookmarks will still not
be supported.

There are providers (the MSDASQL one I think) that will requery the daabase
to allow movefirst behavior, which is why I cringe whenever I see movefirst
in ASP code.

--
Microsoft MVP - ASP/ASP.NET
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