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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Not sure what you mean by parallel spatial calculations.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>In theory most functions in PostGIS can run in parallel assuming they are not restricted by the plan with the exception of most aggregates ( the MVT and ST_MemUnion (which no one uses) and I think possible ST_Extent (have to double check that) are the only aggregates that support parallel. Even those are allowed in subplan nodes. Most functions in PostGIS are marked as safe for parallel so should be able to run in parallel fine.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>But PostgreSQL itself has many restrictions on parallelism – e.g. the cost, the number of tuples before it considers parallel, update/insert statements can't use parallel. These restrictions are slowly being lifted with each new version e.g. 11 supports more kinds of plan nodes and allows CREATE TABLE AS to run in parallel.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Thanks,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Regina<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0in 0in 0in 4.0pt'><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> postgis-users [mailto:postgis-users-bounces@lists.osgeo.org] <b>On Behalf Of </b>David Haynes<br><b>Sent:</b> Wednesday, August 22, 2018 4:10 PM<br><b>To:</b> postgis-users@lists.osgeo.org<br><b>Subject:</b> [postgis-users] parallel spatial calculation<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Hello,<o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I have a few questions regarding parallel spatial calculations.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Since PostgreSQL 10 is allowing for multiple workers is there any work on allowing parallel spatial calculations? Is there anyone potentially looking at VoltDB as a potential place for testing any parallel spatial calculations. VoltDB's spatial capabilities are completely undeveloped but it might be a place to start.<o:p></o:p></p></div></div></div></div></body></html>