<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta name="Generator" content="Microsoft Word 15 (filtered medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri",sans-serif;
mso-fareast-language:EN-US;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:#0563C1;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:#954F72;
text-decoration:underline;}
code
{mso-style-priority:99;
font-family:"Courier New";}
p.msonormal0, li.msonormal0, div.msonormal0
{mso-style-name:msonormal;
mso-margin-top-alt:auto;
margin-right:0cm;
mso-margin-bottom-alt:auto;
margin-left:0cm;
font-size:11.0pt;
font-family:"Calibri",sans-serif;}
span.E-MailFormatvorlage19
{mso-style-type:personal;
font-family:"Calibri",sans-serif;
color:windowtext;}
span.E-MailFormatvorlage20
{mso-style-type:personal;
font-family:"Calibri",sans-serif;
color:windowtext;}
span.E-MailFormatvorlage21
{mso-style-type:personal-reply;
font-family:"Calibri",sans-serif;
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@page WordSection1
{size:612.0pt 792.0pt;
margin:70.85pt 70.85pt 2.0cm 70.85pt;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body lang="DE-CH" link="#0563C1" vlink="#954F72">
<div class="WordSection1">
<p class="MsoNormal"><span lang="EN-GB">Dear QGIS-Developer<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">I am working on a test-server (RAID6) implementing PostgreSQL/PostGIS with vector and raster support. The aim is a big database sharing different data types including high resolution (0.5m, also 0.1m; 8 bit; 3 bands)
rasters and (2m, also 0.5m; 32bit floating point; 1 band) rasters.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">For QGIS 3.16 and 3.22 I can report the following issue.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">When I try to add a PostGIS raster with 32 bit floating point and a resolution of 2m into QGIS the query SELECT ST_SummaryStatsAgg() needs a lot of time at least 10-20 minutes on database.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">Another interesting aspect I observed is that QGIS 3.10.4 loads the same raster nearly instantly.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">I do not understand why a postgis-raster needs 10-20min to load in QGIS 3.16 and 3.22 and QGIS 3.10.4 does not run the above mentioned query on the database.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">Kind regards<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span lang="FR-CH" style="font-size:10.0pt;mso-fareast-language:DE-CH">---<o:p></o:p></span></b></p>
<p class="MsoNormal"><b><span lang="FR-CH" style="font-size:10.0pt;mso-fareast-language:DE-CH">Pascal Bircher<o:p></o:p></span></b></p>
</div>
</body>
</html>