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<p>Hi Linda,</p>
<p>(Mailing lists have had issues lately)</p>
<blockquote type="cite"
cite="mid:nA.Ilib.5alAPaRWMH7.1fIf9P@seznam.cz">
<p>And internally I also have
the full update pipeline implemented - when the dataset is
opened in
<code class="-wm-western">GDAL_OF_UPDATE</code> mode, an
instance of
<code class="-wm-western">OGRMVTWriterDataset</code> is created,
which
allows me to call <code class="-wm-western">DeleteFeature</code>
(D) and
<code class="-wm-western">CreateFeature</code> (I), or a
combination of
both when an existing feature needs to be updated (U). </p>
</blockquote>
Updating an existing feature would normally be done through
SetFeature(), but Delete+Create may be OK for your use case
<blockquote type="cite"
cite="mid:nA.Ilib.5alAPaRWMH7.1fIf9P@seznam.cz"><br>
<p>Given this, I started thinking about an alternative solution
based
on a stable, domain-level identifier such as <code
class="-wm-western">domain_id</code>
(in practice, e.g., <code class="-wm-western">parcel_id</code>),
which is
already known at write time. This would require storing such an
identifier explicitly in the intermediate SQLite table (in
addition
to the internal <code class="-wm-western">idx</code>, geometry,
and tile
coordinates). <code class="-wm-western">DeleteFeature</code>
could then
be implemented by removing all rows associated with that
domain-level
identifier (that would be an input parameter).</p>
</blockquote>
<p>I'm not clear if you intend to submit the changes you mention
upstream, but if so, using your domain-level identifier for
DeleteFeature() wouldn't be appropriate given that DeleteFeature()
is supposed to take the OGR FID as input parameter. So, either you
would need to add logic into the driver to report a domain-level
identifier as the OGR FID (for example through an open option that
would take the name of an attribute), or you would need to
implement a pseudo-SQL command through ExecuteSQL(), like
"DELETE_FEATURE_BY_DOMAIN_ID {domain-level-identifier}"</p>
<p>Even</p>
<pre class="moz-signature" cols="72">--
<a class="moz-txt-link-freetext" href="http://www.spatialys.com">http://www.spatialys.com</a>
My software is free, but my time generally not.</pre>
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