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<DIV dir=ltr align=left><SPAN class=957583818-26012007><FONT face=Arial
color=#0000ff size=2>In the case of a spatial query (the most likely case),
feature readers for providers like SDF and SHP have a list of the feature
IDs that match the query. So the reader can be reset for free. I realize this is
not the case </FONT></SPAN><SPAN class=957583818-26012007><FONT face=Arial
color=#0000ff size=2>for all providers, but the lack of a reset means I have to
pay the select penalty for all providers even though I don't need to for
some.</FONT></SPAN></DIV>
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<FONT face=Tahoma size=2><B>From:</B> fdo-internals-bounces@lists.osgeo.org
[mailto:fdo-internals-bounces@lists.osgeo.org] <B>On Behalf Of </B>Orest
Halustchak<BR><B>Sent:</B> Friday, January 26, 2007 1:36 PM<BR><B>To:</B> FDO
Internals Mail List<BR><B>Subject:</B> RE: [fdo-internals] resetting a feature
reader<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV dir=ltr align=left><SPAN class=662563118-26012007><FONT face=Arial
color=#0000ff size=2>Hi,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=662563118-26012007><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=662563118-26012007><FONT face=Arial
color=#0000ff size=2>Unless the provider internally has cached the results of
the select or provided some other tracking of the select results (e.g. as needed
by the new scrollable feature reader), the provider effectively would have to
re-execute the query anyway. So, I don't think you'd be saving
anything.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=662563118-26012007><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=662563118-26012007><FONT face=Arial
color=#0000ff size=2>Thanks,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=662563118-26012007><FONT face=Arial
color=#0000ff size=2>Orest.</FONT></SPAN></DIV><BR>
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<FONT face=Tahoma size=2><B>From:</B> fdo-internals-bounces@lists.osgeo.org
[mailto:fdo-internals-bounces@lists.osgeo.org] <B>On Behalf Of </B>Traian
Stanev<BR><B>Sent:</B> Friday, January 26, 2007 12:23 PM<BR><B>To:</B>
fdo-internals@lists.osgeo.org<BR><B>Subject:</B> [fdo-internals] resetting a
feature reader<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=673241917-26012007>Hi,</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=673241917-26012007></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=673241917-26012007>How hard would it be
to provide a Reset() capability for the FdoIFeatureReader
interface?</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=673241917-26012007></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=673241917-26012007>The example use for
that would be for two-pass rendering of features.</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=673241917-26012007>I know that one
could re-execute the Select command to get the same reader, but this would in
theory incur a higher penalty, since it would have to redo a spatial query for
example.</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=673241917-26012007></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN
class=673241917-26012007></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN
class=673241917-26012007>Traian</SPAN></FONT></DIV></BODY></HTML>