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    I don't know what is wrong with me today. Here is the response I
    sent in private by accident. Apologies: <br>
    <br>
    <div class="moz-cite-prefix">On 23/09/2020 13:33, Aron Gergely
      wrote:<br>
    </div>
    <blockquote type="cite"
      cite="mid:53304ee7-fe54-753f-3f95-a65e2fc7482d@rasterra.nl">
      <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
      Hi Bernd,<br>
      <br>
      Try blogs? A web search on 'QGIS aggregate functions' used to
      yield me some nice blog resources.<br>
      <br>
      <br>
      For example from Ujaval Gandhi: <br>
      <a class="moz-txt-link-freetext"
        href="https://spatialthoughts.com/2019/04/12/summary-aggregation-qgis/"
        moz-do-not-send="true">https://spatialthoughts.com/2019/04/12/summary-aggregation-qgis/</a><br>
      <a class="moz-txt-link-freetext"
href="https://spatialthoughts.com/2019/04/19/advanced-aggregate-expressions/"
        moz-do-not-send="true">https://spatialthoughts.com/2019/04/19/advanced-aggregate-expressions/</a><br>
      <br>
      Not meaning to single him out of course, some other qgis
      contributors also share great resources! ;)<br>
      <br>
      Best regards,<br>
      Aron<br>
      <br>
      <div class="moz-cite-prefix">On 23/09/2020 13:08, Bernd
        Vogelgesang wrote:<br>
      </div>
      <blockquote type="cite"
        cite="mid:b989eddb-039b-416c-eec6-57952ee948e0@gmx.de"> <br>
        On 23.09.20 10:21, Bernd Vogelgesang wrote: <br>
        <blockquote type="cite"> <br>
          On 23.09.20 09:04, <a class="moz-txt-link-abbreviated"
            href="mailto:Jan.Rutha@STADT-KOELN.DE"
            moz-do-not-send="true">Jan.Rutha@STADT-KOELN.DE</a> wrote: <br>
          <blockquote type="cite">hi there, <br>
            I got a table with a content for streetnames. For example
            the street <br>
            "Mainstreet" ist separated in <br>
            10 different rows of data (one dataset for each letter in
            the word <br>
            "Mainstreet"). <br>
            <br>
            I would like to merge these 10 datasets to one dataset. All
            those <br>
            datasets have one ID - so they qgis should <br>
            be able to search for the same Id and create a new
            textstring with <br>
            all the leters. <br>
            <br>
            I don't know how to practicly implement my idea in QGIS.
            Does anyone <br>
            have an idea for me? <br>
            <br>
            Thanks a lot and I wish you all a good day! <br>
            <br>
            Jan R. <br>
            <br>
            <br>
          </blockquote>
          I think you could try to use an aggregate expression in the
          field <br>
          calculator for a new field. <br>
          <br>
          sth like: <br>
          <br>
          aggregate( <br>
           layer:= 'streets', <br>
           aggregate:='concatenate', <br>
           expression:=name, <br>
           concatenator:='',  <- 2 single quotes, not 1 double, for
          an empty <br>
          concatenator! <br>
           filter:= ID <br>
           ) <br>
          <br>
          I don't know if the filter for ID works in this way. Can't
          check that <br>
          cause I do not own such "interesting" data ;) <br>
          <br>
          Cheers, <br>
          <br>
          Bernd <br>
          <br>
          <blockquote type="cite"> <br>
          </blockquote>
        </blockquote>
        found no way to make my initial aproach work, but this: <br>
        <br>
         array_to_string(array_agg("street",group_by:="ID"),'','') <br>
        <br>
        in the field calculator for a new text field glues together the
        complete <br>
        street name <br>
        <br>
        <br>
        If someone knows a resource with more examples how to work with
        all <br>
        these great functions available, please post it. <br>
        <br>
        <br>
        <blockquote type="cite">
          <blockquote type="cite"> <br>
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        <br>
        Aron Gergely<br>
        +31 (0) 6 38 70 97 66<br>
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