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<p class="MsoNormal">Hi all,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’m having an issue with the planner using a sequential scan instead of the spatial index over a big table with several millions of geometries. My query is similar to this, where the query parameters are the coordinates for a point:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">select * from my table<o:p></o:p></p>
<p class="MsoNormal">where st_contains(geometry, st_setsrid(st_point(x, y), find_srid('public', 'my_table', 'geometry')))<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">This occurs with PostGIS 3.0 ('POSTGIS="3.0.3 3.0.3" [EXTENSION] PGSQL="110" GEOS="3.8.1-CAPI-1.13.3" PROJ="7.1.1" LIBXML="2.9.9" LIBJSON="0.12" LIBPROTOBUF="1.2.1" WAGYU="0.4.3 (Internal)"') on Potgres 11 and 9.6, both for Windows and
fully patched. Works as expected on other instances with Postgres 10 and 12 and PostGIS 2.5.3 and 3.0.3, respectively.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Using other predicates as st_intersection instead of st_contains or reindexing and analyzing the table doesn’t work. Changing find_srid(…) for a constant value uses the expected plan. As a workaround, I’ve extracted the construction of
the second geometry (st_setsrid(…)) to a CTE, giving a plan similar to the expected one.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’m thinking of a different configuration of the plannner in those instances with the problem, but I’m not really sure.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Any help is welcome.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="mso-fareast-language:ES">Thanks in advance,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:ES">Paco Calvo<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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