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<p class=MsoNormal><span style='color:#1F497D'>I haven’t looked that
carefully into GetString but it looks that BinaryReader do some string
buffering.<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>Anyhow, I am talking now only
about single thread use with multiple feature readers.<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>Threading is not issue for that
case.<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>Also, I would like to understand
why SDF provider is not thread safe and to look into possibilities<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>I think that sqlite version used
with SDF allows thread safe access.<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>Thank you for your help,<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>Haris<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
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<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> fdo-internals-bounces@lists.osgeo.org
[mailto:fdo-internals-bounces@lists.osgeo.org] <b>On Behalf Of </b>Gavin Cramer<br>
<b>Sent:</b> Wednesday, August 13, 2008 8:23 PM<br>
<b>To:</b> FDO Internals Mail List<br>
<b>Subject:</b> [fdo-internals] RE: SDF feature reader <o:p></o:p></span></p>
</div>
</div>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span lang=EN-CA style='color:#1F497D'>Yes. The
particular problem that you are seeing can also happen with String values,
since the pointer returned by GetString is to a buffer owned by the
reader. Per-connection threading for any provider (that supports this
kind of threading, as determined by </span><span lang=EN-CA style='font-size:
10.0pt;font-family:"Courier New"'>FdoIConnectionCapabilities::GetThreadCapability</span><span
lang=EN-CA style='color:#1F497D'>) is the way to go.<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-CA style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-CA style='color:#1F497D'>Gavin<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-CA style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-CA style='color:#1F497D'><o:p> </o:p></span></p>
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<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>
fdo-internals-bounces@lists.osgeo.org [mailto:fdo-internals-bounces@lists.osgeo.org]
<b>On Behalf Of </b>Badreddine Karoui<br>
<b>Sent:</b> Wednesday, August 13, 2008 2:18 PM<br>
<b>To:</b> FDO Internals Mail List<br>
<b>Subject:</b> [fdo-internals] RE: SDF feature reader <o:p></o:p></span></p>
</div>
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<p class=MsoNormal><span lang=EN-CA><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>The SDF provider is per
connection threaded which means only one thread can access a reader at a time.
You can have many threads using their own connections/readers at the same time.<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>Badreddine<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
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<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>
fdo-internals-bounces@lists.osgeo.org
[mailto:fdo-internals-bounces@lists.osgeo.org] <b>On Behalf Of </b>Haris
Kurtagic<br>
<b>Sent:</b> Wednesday, August 13, 2008 2:29 PM<br>
<b>To:</b> FDO Internals Mail List<br>
<b>Subject:</b> [fdo-internals] SDF feature reader <o:p></o:p></span></p>
</div>
</div>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Hi,<o:p></o:p></p>
<p class=MsoNormal>I have issue when when more than one feature reader is
created against same SDF connection<o:p></o:p></p>
<p class=MsoNormal>It looks like same buffer ( created by sqlite cursor ) is
shared betwean feature readers.<o:p></o:p></p>
<p class=MsoNormal>This will cause that data returned from feature reader with
function GetGeometry will be corrupted when another reader is used.<o:p></o:p></p>
<p class=MsoNormal>Is this a bug or I am not looking into it correctly ?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I would like to be able to use multi thread access to sqlite
database.<o:p></o:p></p>
<p class=MsoNormal>If I am right, SDF provider is not “thread safe”
? if so, what are main reasons for it ?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Thank you,<o:p></o:p></p>
<p class=MsoNormal>Haris<o:p></o:p></p>
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