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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal>I’d say unitary but I’m scared off by the major changes that would need to be done to collection handling and possible breaking change.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>In the end consistency is most important.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>ST_GeometryN(<>, 4)<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Should return the 4<sup>th</sup> record that ST_Dump returns.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>ST_DumpSegments should either bail with an error or return something for curves.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></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>From:</b> Paul Ramsey <pramsey@cleverelephant.ca> <br><b>Sent:</b> Friday, February 16, 2024 3:45 PM<br><b>To:</b> PostGIS Development Discussion <postgis-devel@lists.osgeo.org><br><b>Subject:</b> Curve Thoughts<o:p></o:p></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The problem of how to deal with curve “decomposition” functions (ST_GeometryN, ST_Dump, ST_DumpRings) in the presence of the various Curve types, and our current inconsistent behaviour with them.<o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><a href="https://gist.github.com/pramsey/cbf6db1edb8762854925f6b6ad6d6b35">https://gist.github.com/pramsey/cbf6db1edb8762854925f6b6ad6d6b35</a><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>What it really comes down to is “are CompoundCurve and CurvePolygon collections or not”. If “not”, if they are unitary, then there are quite a few changes to be made in the behaviour of things like ST_Dump, and other functions that currently just stuff them through collection handling. <o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>So, your answer: unitary? or collection?<o:p></o:p></p></div></div></div></body></html>