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<p class="MsoPlainText"><span lang="EN-US">Hi,<o:p></o:p></span></p>
<p class="MsoPlainText"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoPlainText"><span lang="EN-US">Using QGIS we find that retrieving, rendering and querying/filtering (spatial vector)data from our Oracle databases takes a lot longer than using PostGIS databases.<o:p></o:p></span></p>
<p class="MsoPlainText"><span lang="EN-US">Our DBAs have investigated the matter and finds the performance to be 10-50 times slower in some cases.<o:p></o:p></span></p>
<p class="MsoPlainText"><span lang="EN-US">Using for example Geomedia as GIS application does not show the same issues, and so the Oracle database is most likely not the bottleneck (we have also tested performance directly on the Oracle database, and both Oracle
and PostGIS servers are on the same network, with Oracle on faster hardware).<o:p></o:p></span></p>
<p class="MsoPlainText"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoPlainText"><span lang="EN-US">We believe this could be down to the implementation of how QGIS handles Oracle connections.
<o:p></o:p></span></p>
<p class="MsoPlainText"><span lang="EN-US">If this is indeed the case, and an improvement is more of a feature request than an actual bug, we would be happy to discuss sponsoring the development in some way.<o:p></o:p></span></p>
<p class="MsoPlainText"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoPlainText"><span lang="EN-US">We are using Oracle 12C, PostGIS 2.3 on Postgresql 9.5/9.6 and QGIS 2.18.x<o:p></o:p></span></p>
<p class="MsoPlainText"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoPlainText"><span lang="EN-US">Any other input or questions on the matter are of course welcome
</span><span lang="EN-US" style="font-family:Wingdings">J</span><span lang="EN-US"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:8.0pt;font-family:"Tahoma","sans-serif";mso-fareast-language:DA">Kind regards<br>
<br>
<b>Niels Kjær</b> <br>
IT-architect<br>
</span><span style="mso-fareast-language:DA"><a href="mailto:nikja@sdfe.dk"><span lang="EN-US" style="font-size:8.0pt;font-family:"Tahoma","sans-serif"">nikja@sdfe.dk</span></a></span><span lang="EN-US" style="font-size:8.0pt;font-family:"Tahoma","sans-serif";mso-fareast-language:DA">
<br>
<br>
</span><span style="font-size:8.0pt;font-family:"Tahoma","sans-serif";mso-fareast-language:DA"><img border="0" width="74" height="71" id="Billede_x0020_2" src="cid:image001.png@01D2CF17.C4D693C0" alt="SDFE_RGB_DK (Custom)"></span><span lang="EN-US" style="font-size:8.0pt;font-family:"Tahoma","sans-serif";mso-fareast-language:DA"><br>
Agency for data supply and efficiency<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:8.0pt;font-family:"Tahoma","sans-serif";mso-fareast-language:DA"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:8.0pt;font-family:"Tahoma","sans-serif";mso-fareast-language:DA">Rentemestervej 8
<br>
DK-2400 Copenhagen NV <o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:8.0pt;font-family:"Tahoma","sans-serif";mso-fareast-language:DA">Denmark<br>
</span><span style="mso-fareast-language:DA"><a href="http://www.sdfe.dk/"><span style="font-size:8.0pt;font-family:"Tahoma","sans-serif"">www.sdfe.dk</span></a></span><span style="font-size:8.0pt;font-family:"Tahoma","sans-serif";mso-fareast-language:DA">
</span><span style="mso-fareast-language:DA"><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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