Re: Issue with st_estimatedextent function ??

Bo Victor Thomsen <[email protected]> Wed, 19 Nov 2025 20:44:17 +0100
Newsgroups gmane.comp.gis.postgis
Message-ID <[email protected]>
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Hi Paul -

And thank /you/ for the very quick answer ! I followed you advice and 
upgraded to PostGIS 3.5.3. And lo and behold: It worked !!

(And I'm sorry for /not/ looking in PostGIS bug-tracker before blasting 
out unnecessary mails to the list - and wasting your time) .

Med venlig hilsen / Best regards

Bo Victor Thomsen

On 19/11/2025 19.36, Paul Ramsey wrote:
> I cannot replicate this bug on my PostGIS 3.5.5dev environment, 
> probably because the issue is already fixed as of 3.5.3
>
> https://github.com/postgis/postgis/blob/stable-3.5/NEWS#L66
> https://trac.osgeo.org/postgis/ticket/5819
>
> I think you probably need a maintenance upgrade.
>
> ATB,
> P
>
> On Wed, Nov 19, 2025 at 9:21 AM Bo Victor Thomsen 
> <[email protected]> wrote:
>
>     Hi list -
>
>     I'm using Postgres/Postgis as a data repository for QGIS - and it
>     normally just works.. However I'm getting errors with tables
>     having long names, for example:
>     /*
>     fdc_results.bygningskade_stormflod_rcp85_2100_t100_ssp3_7_0_20251119164
>
>     */
>     (Schema-name length: 11, table-name length: 59)
>
>     I have tracked the issue using the log facility in QGIS. It shows,
>     that QGIS intermittently executes a SQL command:
>
>     /*SELECT
>     st_estimatedextent('fdc_results','bygningskade_stormflod_rcp85_2100_t100_ssp3_7_0_20251119164','geom')*/
>
>     which results in an error: *ERROR: invalid name syntax*
>
>     If I change the table name to:
>
>     /*fdc_results.bygningskade_stormflod_rcp85_2100_t100_ssp3_7_0
>     */(Schema-name length: 11, table-name length: 47)
>
>     the error disappears.
>
>     I've done some testing and could replicate the error (and
>     non-error) situation in PGAdmin
>
>     Further testing shows that if the sum of the character lengths of
>     the schema- and table-name is larger than 58 the function will
>     stop with an error. Otherwise it returns a result like:
>
>     "BOX(716701.25 6167151,720533.9375 6174220)"
>
>     It's my understanding, that the maximum length of a tablename in
>     PostgreSQL is 63. This same limit applies for every type of
>     identifier in Postgres. Am I wrong to assume this? Or is there an
>     issue with name lengths in
>     the PostGIS st_estimatedextent/**/ function??
>
>     (It might be a coincidence but if you express the tablename like
>     this :
>     /*"*//*fdc_results"."bygningskade_stormflod_rcp85_2100_t100_ssp3_7_0*//*",
>     */the total length is 63)
>
>     PostgreSQL version: "PostgreSQL 17.4 on x86_64-windows, compiled
>     by msvc-19.42.34436, 64-bit"
>
>     PostGIS version: "3.5 USE_GEOS=1 USE_PROJ=1 USE_STATS=1"
>
>     -- 
>     Med venlig hilsen / Best regards
>
>     Bo Victor Thomsen
>
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    <p>Hi Paul -</p>
    <p>And thank <i>you</i> for the very quick answer ! I followed you
      advice and upgraded to PostGIS 3.5.3. And lo and behold: It worked
      !!</p>
    <p>(And I'm sorry for <i>not</i> looking in PostGIS bug-tracker
      before blasting out unnecessary mails to the list - and wasting
      your time) .</p>
    <pre class="moz-signature" cols="72">Med venlig hilsen / Best regards

Bo Victor Thomsen</pre>
    <div class="moz-cite-prefix">On 19/11/2025 19.36, Paul Ramsey wrote:<br>
    </div>
    <blockquote type="cite"
cite="mid:CACowWR3eu0KdVWqrZh+=JMUSg7J4GqzN-BSFcXoSQF2hw0VTkA@mail.gmail.com">
      <meta http-equiv="content-type" content="text/html; charset=UTF-8">
      <div dir="ltr">I cannot replicate this bug on my PostGIS 3.5.5dev
        environment, probably because the issue is already fixed as of
        3.5.3
        <div><br>
        </div>
        <div><a
href="https://github.com/postgis/postgis/blob/stable-3.5/NEWS#L66"
            moz-do-not-send="true" class="moz-txt-link-freetext">https://github.com/postgis/postgis/blob/stable-3.5/NEWS#L66</a></div>
        <div><a href="https://trac.osgeo.org/postgis/ticket/5819"
            moz-do-not-send="true" class="moz-txt-link-freetext">https://trac.osgeo.org/postgis/ticket/5819</a><br>
        </div>
        <div><br>
        </div>
        <div>I think you probably need a maintenance upgrade.</div>
        <div><br>
        </div>
        <div>ATB,</div>
        <div>P</div>
      </div>
      <br>
      <div class="gmail_quote gmail_quote_container">
        <div dir="ltr" class="gmail_attr">On Wed, Nov 19, 2025 at
          9:21 AM Bo Victor Thomsen &lt;<a
            href="mailto:[email protected]"
            moz-do-not-send="true" class="moz-txt-link-freetext">[email protected]</a>&gt;
          wrote:<br>
        </div>
        <blockquote class="gmail_quote"
style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex">
          <div>
            <p>Hi list - </p>
            <p>I'm using Postgres/Postgis as a data repository for QGIS
              - and it normally just works.. However I'm getting errors
              with tables having long names, for example: <br>
              <i><b><br>
fdc_results.bygningskade_stormflod_rcp85_2100_t100_ssp3_7_0_20251119164 <br>
                </b></i><br>
              (Schema-name length: 11, table-name length: 59)</p>
            <p>I have tracked the issue using the log facility in QGIS.
              It shows, that QGIS intermittently executes a SQL
              command: </p>
            <p><i><b>SELECT
st_estimatedextent('fdc_results','bygningskade_stormflod_rcp85_2100_t100_ssp3_7_0_20251119164','geom')</b></i></p>
            <p>which results in an error: <b><span
style="color:rgb(34,34,34);font-family:&quot;Source Code Pro&quot;,SFMono-Regular,Menlo,Monaco,Consolas,&quot;Liberation Mono&quot;,&quot;Courier New&quot;,monospace;font-size:12px;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;letter-spacing:0.14994px;text-align:start;text-indent:0px;text-transform:none;word-spacing:0px;white-space:pre-wrap;background-color:rgb(255,255,255);text-decoration-style:initial;text-decoration-color:initial;float:none;display:inline">ERROR:  invalid name syntax</span></b></p>
            <p>If I change the table name to:</p>
            <p><i><b>fdc_results.bygningskade_stormflod_rcp85_2100_t100_ssp3_7_0 
                   </b></i>(Schema-name length: 11, table-name length:
              47) </p>
            <p>the error disappears. </p>
            <p>I've done some testing and could replicate the error (and
              non-error) situation in PGAdmin</p>
            <p>Further testing shows that if the sum of the character
              lengths of the schema- and table-name is larger than 58
              the function will stop with an error. Otherwise it returns
              a result like:</p>
            <p>"BOX(716701.25 6167151,720533.9375 6174220)"</p>
            <p>It's my understanding, that the maximum length of a
              tablename in PostgreSQL is 63. This same limit applies for
              every type of identifier in Postgres. Am I wrong to assume
              this? Or is there an issue with name lengths in the PostGIS st_estimatedextent<i><b>
                </b></i> function?? </p>
            <p>(It might be a coincidence but if you express the
              tablename like this : <i><b>"</b></i><i><b>fdc_results"."bygningskade_stormflod_rcp85_2100_t100_ssp3_7_0</b></i><i><b>", </b></i>the
              total length is 63) </p>
            <p>PostgreSQL version: "PostgreSQL 17.4 on x86_64-windows,
              compiled by msvc-19.42.34436, 64-bit"</p>
            <p>PostGIS version: "3.5 USE_GEOS=1 USE_PROJ=1 USE_STATS=1"</p>
            <pre cols="72">-- 
Med venlig hilsen / Best regards

Bo Victor Thomsen</pre>
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